RN-BT-DATA-UG

Bluetooth Data Module Command
Reference & Advanced Information
User’s Guide
MODULES:
RN24
RN25
RN41
RN42
RN41XVRN42XVSERIAL ADAPTERS:
RN220XP
RN240
RN270
RN274
© 2013 Roving Networks. All rights reserved.
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Copyright © 2013 Roving Networks. All rights reserved. Apple Inc.,
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time. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
Roving Networks assumes no liability for applications assistance or customer’s product design. Customers are responsible for their products andapplications that use Roving Networks components. To minimize customer product risks, customers should provide adequate design and operating safeguards.
Roving Networks, Inc.
102 Cooper Court
Los Gatos, CA 95032+1 (408) 395-5300
www.rovingnetworks.com

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Roving Networks products are not authorized for use in safety-criticalapplications (such as life support) where a failure of the Roving Networks
product would reasonably be expected to cause severe personal injury or
death, unless officers of the parties have executed an agreement specifically governing such use.

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Table of Contents
Chapter 1. Introduction
1.1 Overview ........................................................................................................ 5
1.2 Evaluation Boards & Reference Designs ....................................................... 5
1.3 Command Mode vs. Data Mode ..................................................................... 6
1.4 Operating Modes .......................................................................................... 10
1.5 Using Dipswitches & GPIO Pins for Configuration ....................................... 11
1.6 Making a Bluetooth Connection ................................................................... 12

Chapter 2. Command Reference
2.1 Command Syntax ......................................................................................... 19
2.2 SET Commands ........................................................................................... 19
2.3 GET Commands ........................................................................................... 31
2.4 Change & Action Commands ....................................................................... 32
2.5 GPIO Commands ......................................................................................... 37

Chapter 3. Advanced Topics
3.1 Power Management ..................................................................................... 41
3.2 Configuration Timer Settings ........................................................................ 44
3.3 Interfacing to a Microprocessor .................................................................... 45
3.4 HCI Mode ..................................................................................................... 45
3.5 Profile Settings & Features ........................................................................... 46
3.6 Using GPIO Pins as Modem Control Signals ............................................... 47
3.7 Design Concerns .......................................................................................... 47
3.8 Serial Adapter Configuration ........................................................................ 52
3.9 Null Modem & Flow Control Jumpers ........................................................... 53
3.10 Dipswitch Settings ...................................................................................... 54

Chapter 4. Applications
4.1 Instant Cable Replacement .......................................................................... 57

Chapter 5. HID Profile
5.1 Overview ...................................................................................................... 59
5.2 HID Firmware Overview ............................................................................... 60
5.3 HID Reports .................................................................................................. 62
5.4 HID References ............................................................................................ 68

Appendix A. Factory Defaults
Appendix B. Command Quick Reference Guide
Appendix C. Firmware Revision History
C.1 Version 6.15 (3/26/2013) ............................................................................. 75
C.2 Version 6.12 (Limited Release) ................................................................... 75
C.3 Version 6.11 ................................................................................................. 75

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C.4 Version 6.10 ................................................................................................. 75
C.5 Version 4.77 (8/10/2009) ............................................................................. 76
C.6 Version 4.74 (3/7/2009) ............................................................................... 76

Appendix D. Document Information

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Chapter 1. Introduction
1.1

OVERVIEWThis document contains the software command reference and advanced configuration
settings for Roving Networks Bluetooth data modules. The document is applicable toall Bluetooth data modules modules (such as the RN41 and RN42), and USB dongles.
Commands and settings that are specific to a single product or product family are identified as such in the document.
You configure Roving Networks Bluetooth devices over the Bluetooth link or over themodule’s UART using a simple ASCII command language. Set commands configure
the module and get commands echo the current configuration. Configuration settings
modified with set commands do not take effect until the module has been rebooted,
even though the get command may show otherwise.
This document assumes that you have a working knowledge of Bluetooth operationand communications. To configure the Roving Networks modules you need a Bluetooth-enabled PC (either built-in or using a USB Bluetooth dongle). You can only configure one module at a time. Once configured, module settings are saved (independentof power down) until they are explicitly changed or the factory defaults are restored.

NOTICE TO CUSTOMERSThe commands and applications described in this document apply to Roving Networks
Bluetooth data modules, e.g., RN41 and RN42. For Bluetooth audio module configuration
information (e.g., RN52), refer to the Bluetooth Audio Module Command Reference User’s
Guide.

1.2

EVALUATION BOARDS & REFERENCE DESIGNSRoving Networks provides a variety of boards, kits, and reference designs that you can
use for evaluation and prototyping.
The RN-41-EK and RN-42-EK evaluation boards are field-ready, Bluetooth SIG qualified prototyping platforms for the RN41 and RN42 modules, respectively. The boards
have the flexibility to connect directly to PCs via a standard USB interface (via the FTDI
chipset) or to embedded processors through the TTL UART interface. The status LEDs,
dipswitches, and signal headers enable demonstrations and proofs of concept.
The Bluetooth HID reference design is implemented in the RN42HID-I/RM module. The
Bluetooth HID profile is typically used in applications such as keyboards, mice, andgame controllers. To demonstrate the basic capability of the Bluetooth HID profile, Roving Networks has developed a Bluetooth reference design implemented in the
RN42HID-I/RM module. The reference design operates in three modes:• Presenter mode—Used for presentation software such as Microsoft Powerpoint• Music mode—Music controller for products such as the iPod, iPhone, and iPad
• Custom mode—You can configure each button to send a sequence of up to 4
keys

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For more information on available evaluation boards and reference designs, refer to the
Roving Networks web site.

1.3

COMMAND MODE VS. DATA MODE
The Bluetooth module operates in two modes: data mode (default) and commandmode. While in data mode, the module operates as a data pipe. When the module
receives data, it strips the Bluetooth headers and trailers and passes the user data to
the UART port. When data is written to the UART port, the module constructs the Bluetooth packet and sends it out over the Bluetooth wireless connection. Thus, the entire
process of sending/receiving data to the host is transparent to the end microprocessor.
See Figure 1-1.

FIGURE 1-1:

DATA & COMMAND MODES
Host

BluetoothUser DataA

B

Bluetooth
ModuleUART$$$

Bluetooth Interface

A

B

$$$
CommandMode

The default configuration for the Bluetooth module is:• Bluetooth slave mode
• Bluetooth pin code 1234
• Serial port 115,200 Kbps baud rate, 8 bits, no parity, 1 stop bit• Serial port flow control disabled• Low power mode off
You configure the module by putting it into command mode (see “Enter CommandMode” on page 8) and sending ASCII commands over the UART port or the Bluetooth
link. You reboot the module so that the settings take effect. Once you change the configuration parameters, they persist until you change them or you perform a factory
reset.
There are two ways to configure the Bluetooth module:• Local configuration using your computer’s serial port
• Via Bluetoothwww.rovingnetworks.com

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You need a terminal emulator to complete the setup.
Note:

1.3.1

Use either the TeraTerm (Windows OS) or CoolTerm (Mac OS-X) terminal
emulator program.

Configuring the Module over the UART Port

Connect the module to your computer. You can connect using the RS-232 DB9 port orvia a USB cable. For example, if you are using the RN-41-EK evaluation board, connect it to your computer using a USB cable.
With the Bluetooth module connected and powered on, run a terminal emulator andopen the COM port to which the cable is connected. The terminal emulator’s communication settings should be the default serial port settings:• Baud rate 115,200 kbps
• 8 bits• No parity• 1 stop bit• Hardware flow control enabled
Note:

You can use local configuration at any time when the module does NOT
have a Bluetooth connection, as well as under certain conditions. If themodule is in configuration mode and a connection occurs, the module exits
configuration mode and data passes back and forth from the remote module.

Once a connection is made, you can only enter command mode if the boot-up configuration timer has not expired (60 seconds). To remain in configuration mode, set theconfiguration timer to 255. See “Configuration Timer Settings” on page 44 for more
information.
Note:

If the module is in Auto-Connect Master Mode, you cannot enter commandmode when connected over Bluetooth. See “Operating Modes” on page 10
for more information on the various operating modes.

Refer to “Enter Command Mode” on page 8” for information on entering commandmode from a terminal emulator.

1.3.2

Remote Configuration Using Bluetooth

It is often useful to configure the module remotely over a Bluetooth connection. Before
performing remote configuration using Bluetooth, first pair the Bluetooth module withyour computer. For PCs with Bluetooth capability and running Windows, click Bluetooth devices in the system tray at the bottom right of your computer screen. SelectAdd a Bluetooth device and follow the on-screen instructions. For Mac OS-X, click
the Bluetooth icon, select Set up Bluetooth device, and follow the on-screen instructions.
Once a connection is made, you can only enter command mode if the boot-up configuration timer has not expired (60 seconds). To remain in configuration mode, set theconfiguration timer to 255. See “Configuration Timer Settings” on page 44 for more
information.

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When you are finished configuring, reset the module or send the --- command, whichcauses the module to exit configuration mode and allows data to pass normally.
Note:

1.3.3

Configuration mode (local or remote) is NEVER enabled when the module
is in auto-mode and is connected over Bluetooth.

Enter Command Mode

To enter command mode, launch a terminal emulator and specify the module’s default
settings. Table 1-1 shows the serial port settings.
TABLE 1-1:
SERIAL PORT SETTINGS
Setting

Value

Port

COM port to which you attached the module

Baud rate

115200

Data rate

8 bitsPatiryNone

Stop bits

1

Flow control

None

Type $$$ into the terminal emulator to enter command mode.
The module returns the string CMD, which indicates that your connection and terminal
settings are correct. While in command mode, the module accepts ASCII bytes as commands. When you enter a valid command, the module returns AOK. It returns ERR for aninvalid command and ? for unrecognized commands. Type h <cr> to see a list of commands.
A quick check to confirm that you are in command mode is to type the X <cr> command
after entering command mode. This command shows the a summary of the module’s
current settings, such as the Bluetooth name, device class, and serial port settings.
See Figure 1-2.
To return to data mode, type --- <cr> or reset the module and re-connect.
Note:www.rovingnetworks.com

The module supports a fast data mode. In this mode, the module does not
go into command mode even if it receives $$$. If you do not enter commandmode within the configuration window (60 seconds), the module enters fast
data mode. See “ST,<value>” on page 26 and “Configuration Timer Settings” on page 44 for more information on setting the configuration window.

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FIGURE 1-2:

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VIEW CURRENT SETTINGS

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1.4

OPERATING MODES
The Bluetooth module has several operating modes, which you set using the SM command in command mode.
Note:

In all master modes, the module cannot be discovered or configured
remotely over Bluetooth.

• Slave Mode (SM,0)—Default mode, in which other Bluetooth devices can discoverand connect to the module. You can also make outbound connections in thismode.
• Master Mode (SM,1)—In this low-speed connection mode, the module makes
connections when a connect command (C) is received. This command can also
contain the Bluetooth address of the remote device. If a device is not specified,
the module uses the stored remote address. The connection can be broken if thespecial break character or string is sent (use the SO command to set the breakcharacter). This mode is useful when you want the module to initiate connections(not receive them). In this mode, the module is NOT discoverable or connectable.
• Trigger Mode (SM,2)—In this low-speed connection mode, the module makes
connections automatically when a character is received on the serial port (UART).
The connection continues as long as characters are received on either end. The
module has a configurable timeout (which you set using the ST command) that
disconnects the module after the specified number of seconds of inactivity (1 to255) or a configurable break character is received.
• Auto-Connect Master Mode (SM,3)—In this mode, the module makes connections automatically on power-up and re-connects when the connection is lost. Thismode can be set by command, or by setting the external dipswitch 3 during powerup (evaluation kits) or by driving GPIO6 high (Bluetooth modules). If an address is
not stored, the module performs an inquiry process and the first device found thatmatches the COD is stored. In this mode, high-speed data is passed without being
interpreted; therefore, the connection cannot be broken via commands or software break characters. If a disconnect occurs, the module attempts to re-connect
until successful.
• Auto-Connect DTR Mode (SM,4)—This mode must be set by command. It operates like Auto-Connect Master Mode, except that you control connection and disconnection with dipswitch 3 (evaluation kits) and GPIO6 (Bluetooth modules).
Turning the dipswitch on or driving GPIO6 high initiates the auto-connect process;turning the dipswitch off or driving GPIO6 low causes a disconnect.
• Auto-Connect ANY Mode (SM,5)—This mode must be set by command. Thismode operates like Auto-Connect DTR Mode, except that each time the dipswitch
or GPIO is set, an inquiry is performed and the first device found is connected.
The stored address is NOT used, and the address found is never stored.
• Pairing Mode (SM,6)—In this mode, the module attempts to connect with theremote device matching the store remote address. You set the remote addressusing the SR command.

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1.5

USING DIPSWITCHES & GPIO PINS FOR CONFIGURATIONThe Bluetooth modules have dipswitches (for evaluation kits) or GPIO pins (for modules) that you can use to configure the module. See Table 1-2.

TABLE 1-2:
Function

DIPSWITCH & GPIO SETTINGS
Dipswitch(Adpaters & GPIO Pin
Evaluation (Modules)
Boards)

Factory Reset

1

GPIO4

Settings (OFF = 0 VDC/ON = 3 VDC)
Off = disabled, on = armed.
Set this dipswitch/GPIO pin on power up to arm the reset function. Then
toggle the module off and on three times to reset all settings to the factory defaults (other than the Bluetooth name).

Auto Discovery/
Pairing

2

GPIO3

Off = disabled, on = enabled.
You use these settings in conjunction with dipswitch 3/GPIO6. If
dipswitch 3/GPIO6 are also set, the module performs a device inquiry
scan, searching for a partner device with a special matching class(0x55AA). Once it finds this device, it stores the address into the remoteaddress field and auto-connects to the remote device.
If dipswitch 3/GPIO6 are NOT set, the module enters slave mode withthe special matching class and waits for the master to find it. This modeis usually set once on both ends of a module pair (for instant cablereplacement) and then removed.

Auto-Connect

3

GPIO6

Off = disabled, on = enabled.
This setting is equivalent to Auto-Connect Master Mode in software. The
module connects to the stored address. If dipswitch 2/GPIO3 is also set,a new discovery/pairing can be made.
If connected via the CFR command, toggling the dipswitch off-on-off terminates the current connection.

Baud Rate

4

GPIO7

Off = stored setting (115 K), on = 9,600.
This setting is used to configure 9,600 or a software selected (default =115 K) baud rate. If the dipswitch is off, the module uses the stored
baud rate setting. When the dipswitch is on, the baud rate is set to 9,600
regardless of the software setting.

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Table 1-3 describes the GPIO pin assignments for Roving Networks Bluetooth hardware. Refer to “GPIO Commands” on page 37 for more information on the commands
you use to configure the GPIO pins.
TABLE 1-3:

GPIO ASSIGNMENTS
RN4x, RN4xXV,
RN220, RN270,
RN-XV-EK,
RN-XV-RD1/2

GPIO

RN-4X-EK

RN-BT-HID-RD1

Firmware

4.77

6.xx

6.11-HID DEMO

GPIO2

–

–

IN: (B7) power on/off, left arrow, iOS
keyboard toggle

GPIO3

IN: (dipswitch 2), discovery/auto-pairread at power up, DCD in DUN andMDM profile–

IN: (B3) Custom, down arrow

GPIO4

IN: (dipswitch 1), factory default

IN: (dipswitch 1), factory default

IN: presentation (B1)

GPIO5

OUT: system status (green LED)

OUT: system status (green LED)

OUT: system status (green LED)

GPIO6

IN: (dipswitch 3), auto connect readat power up, DSR in DUN and MDM
profile–IN: factory reset (B4)

GPIO7

IN: (dipswitch 4), baud rate select on
power up, CTS in DUN and MDM
profile–IN: (B3), music

OUT: over the air TX activity (blue
LED)

–

GPIO8
GPIO9

OUT: fire relay A on RD1––

GPIO10––

IN: pull high connect to stored Bluetooth address; pull low disconnect if
connected
OUT: (B6), SPP, FAST-FWD

GPIO11––

IN: on power up if high, HID profile isselected AND if bit 9 in HID flag is set(SH,<value>)

1.6

MAKING A BLUETOOTH CONNECTION
By default, the Bluetooth module acts as a slave and the PC or smartphone is the master. You connect to the Bluetooth module using the Bluetooth device manager, which
varies depending on your smartphone or computer’s operating system. In all cases, theprocess is the same:• Discovery—In the discovery phase, the Bluetooth module broadcasts its name,profile support, and MAC address. It is ready for other devices to pair with it. Discovery is only availoable in slave mode.
• Pairing—During pairing, the Bluetooth module and the Bluetooth master validate
the pin code. If the pin code validates successfully, they exchange security keys
and a channel hopping pseudo-random sequence. Successful pairing results inthe module and master establishing link keys.
• Connecting—Before connecting, the Bluetooth devices must have paired successfully. The master initiates a connection, the master and slave validate the link
keys, and a Bluetooth link is established.
The following sections describe these processes in detail.

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1.6.1

Discovery

When you turn on the Bluetooth module, it is discoverable. For evaluation kits, thegreen LED blinks, indicating that it is discoverable. Open your PC’s Bluetooth device
manager and choose to add a new device. The Bluetooth device manager’s icon is
located in the bottom right corner of your screen in the taskbar for Windows and in theupper right corner for Mac OS-X. The Bluetooth device manager displays a list of discoverable Bluetooth devices (see Figure 1-3). The Bluetooth module displays as SerialPort Profile (SPP) Service FireFly-ABCD, where FireFly is the type of Roving Networks module and ABCD is the last four nibbles of the Bluetooth MAC address. (Youcan change the local device name).
FIGURE 1-3:

1.6.2

DISCOVER THE BLUETOOTH MODULE

Pairing

To pair with the module, double-click the module’s name (i.e., FireFly-XXXX) in the list.
The firmware automatically stores up to 8 pairings from remote hosts in a first in, firstout fashion.
Choose to enter the module’s pairing code (see Figure 1-4) and enter the default pin
code, 1234. When the Bluetooth device manager completes pairing, it issues a message that the Bluetooth device is installed on COMX where COMX is unique to yourcomputer. In some cases, the Bluetooth device manager creates two COM ports; in thissituation, only use the COM port labeled “outgoing.”

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FIGURE 1-4:

Note:

PAIR WITH THE BLUETOOTH MODULE

You only need to pair with the module once.

Figure 1-5 shows example COM port settings.

FIGURE 1-5:

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BLUETOOTH COM PORT SETTINGS

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If the remote Bluetooth device does not require authentication, a connection can occur
without the pairing process. However the Bluetooth specification requires that if either
device involved in the pairing process requires authentication, the other device must
participate to ensure a secure link. Roving Networks modules default to an open mode,such that the module does NOT require authentication. However, most PCs requireauthentication. See “Security Modes” on page 17 for more information on using passkeys.
Once connected, the module is in data mode allowing data to flow in both directions as
if the serial port were locally attached to the PC. For configuration, the module must be
in command mode. See “Enter Command Mode” on page 8 for more information.
Note:

1.6.2.1

Only one client can connect to a slave module at a time. As a master, themodule can make multiple connections, but only in a point-to-point, serialized fashion. Roving Networks modules do not currently support multi-point
master mode.
PAIRING WITH A COMPUTER OR SMART PHONE

The module may use simple secure pairing (SSP) if it is attempting to pair with devices
that support the Bluetooth specification version 2.1 + EDR. SSP does not require theuser to remember the pin code, but it asks to confirm the 6-digit number if the device
has a display capability.

1.6.3

Connecting

In most cases, you connect from another device to the module as an outgoing Bluetooth connection. You can also make an incoming connection in which the evaluation
board initiates the connection to the remote device.
1.0.0.1

Outgoing Connections

To establish an outgoing Bluetooth connection from a PC to the module, open the module’s outgoing COM port from your application or a terminal emulator. The module
remains connected until you close the COM port or remove power from the board.
Once connected, the module is in data mode allowing data to flow in both directions.
For configuration, the module must be in command mode. See “Enter CommandMode” on page 8 for more information.
Note:

1.0.0.2

Only one client can connect to a slave module at a time. As a master, themodule can make multiple connections, but only in a point-to-point, serialized fashion. Roving Networks modules do not currently support multi-point
master mode.
Incoming Connections

For an incoming connection you use the port specified in your Bluetooth settings asincoming (refer back to Figure 1-3). In incoming connections, the PC or host listens for
an incoming connection from the remote Bluetooth device, in this case the module.
Perform the following steps to make in incoming connection.
1. You need the MAC address of the PC’s Bluetooth radio to connect from the module to the host PC. Open the PC’s Bluetooth advanced settings to find the MAC
address. See Figure 1-6.

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FIGURE 1-6:

PC’S BLUETOOTH RADIO MAC ADDRESS

2. Pair your module with the PC as described in “Pairing” on page 13.
3. Open a terminal (called terminal A in this example) and connect it to the module.
You can run this terminal on the host PC or another computer.
4. Open a second terminal (called terminal B in this example) on the host PC to listen for the incoming Bluetooth connection using the incoming COM port number.
5. Type C,<MAC address> <cr> in terminal A to establish an SPP connection to thehost PC. See Figure 1-7 for an example connection.
6. Try the following commands:• $$$ to enter command mode
• SO,% to enable status message to see connect/disconnect conditions• R,1 to reboot• $$$ to re-enter command mode
• + to enable local echo
• C,<MAC address> to attempt a connection with remote device
Characters you type in terminal B are sent over Bluetooth to the host PC andappear in terminal A. Any characters entered in terminal A are transmitted to terminal B.
7. To kill the connection, type the k,1 <cr> command in terminal B.

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FIGURE 1-7:

1.6.4

TERMINALS A & B

Security Modes

The Bluetooth module supports authentication. If the local or remote Bluetooth device
has authentication enabled, a pin code is required the first time a connection is
attempted. The pin code is a series of numbers or characters from 1 to 16 charactersin length.
Note:

The default pin code for Roving Networks Bluetooth modules is 1234. The
RN-41-EK and RN-42-EK evaluation boards do not require a pin code.

After you enter the pin code, the Bluetooth devices compare them. If they match, a link
key is generated and stored. Usually, but not always, the remote device stores the link
key. For subsequent connections, the devices compare link keys. If they are correct,
you do not need to re-enter the pin code.

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If the remote device is a PC or PDA, the user generally is prompted to enter this pin
code. To remove the stored link key on the remote device, you typically “unpair” or
remove the device from the Bluetooth manager. You can change the pin code toremove the link key on the Bluetooth module, forcing a new pin code exchange to occur
upon subsequent connection attempts.
Note:www.rovingnetworks.com

Only one master can connect to the Bluetooth module at a time.

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Chapter 2. Command Reference
Roving Networks Bluetooth modules support a variety of commands for configuration.
This section describes these commands in detail and provides examples.

2.1

COMMAND SYNTAX
To issue commands to the module, you send a keyword followed by optional parameters.
• All commands are one or two characters and can be upper or lower case.
• Delimit command arguments with a comma.
• Commands use decimal input, except where noted.
• Text data, such as the Bluetooth name and pin code, is case sensitive.
• All commands only take effect AFTER reboot, except where noted.
There are five general command categories, as shown in Table 2-1.

TABLE 2-1:

COMMAND TYPES

Command Type

Description

Set commands

Store information to flash memory. Changes take effect after a power cycle or reboot.

Get commands

Retrieve and display the stored information.

Change commands

Temporarily change the value of various settings such as serial baud rate, parity, etc.

Action commands

Perform actions such as inquiries, connecting, etc.

GPIO commands

Configure and manipulate the GPIO signals.

2.2

SET COMMANDS
The set commands specify configuration settings and take effect after power cycling or
rebooting.

2.2.1

S7,<flag>This command enables/disables 7-bit data mode, where <flag> is shown in Table 2-2.
TABLE 2-2:
7-BIT DATA MODE VALUES
Flag

Default:

Description

0

Disable.

1

Enable.

0// Enable 7-bit data mode

Example: S7,1

2.2.2

SA,<value>

The set authentication command forces authentication when a remote device attempts
to connect, where <value> is one of the values shown in Table 2-3. Regardless of thissetting, if a remote device forces authentication, this device responds with the stored

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pin code. Once a remote device has exchanged pin codes with this device, a link key
is stored for future use. The device stores up to 8 keys automatically and permanently
in flash memory, in a first in, first out fashion.
TABLE 2-3:

SET AUTHENTICATION VALUES

Value

Description

0Open mode. With this mode, the module uses Bluetooth version 2.0 with NO encryption (open mode). Thismode is useful for legacy devices that do not need security. This mode is the same as in firmware version 4.77.

1

SSP keyboard I/O mode (default). If this option is set, the remote host receives a prompt; reply yes to pair.
For Android devices, the user is prompted with a 6-digit code and is asked to verify that the code matcheson the module. The module always responds yes. Because the module cannot display a code, simply
press OK or Yes on the remote device to authenticate.

2

SSP “just works” mode. This mode works with iOS device and newer PCs. You can use this mode with
Droid devices if the application connects using unsecure mode (which was the default on Droid version
3.3). This mode also works with new PC stacks.

4

Pin code. Forces pin code mode authentication (Bluetooth version 2.0), which requires the host device toenter a pin code that matches the stored pin code. The functionality is similar to firmware version 4.77.

Note:

Default:

Modes 0 and 4 are legacy modes that do not support SSP (Bluetooth version 2.0).
1

Example: SA,1

2.2.3// Enable authentication

SB,<value>

When you issue the set break command, the device sends a break signal immediately
where <value> is the length of the break signal in milliseconds as shown in Table 2-4.
The break signal on the UART TX pulls the line low.
TABLE 2-4:
SET BREAK VALUESDefault:

Value

Break Length (ms)

1

37

2

18.5

3

12

4

9

5

7

6

6

N/A

Example: SB,1

2.2.4// Send a break signal of 37 ms

SC,<value>

This command sets the service class field in the class of device (COD). The service
class consists of the most significant 11 bits in the COD. This command sets the MSW
to create the 24-bit device class number. The inquiring device interprets the service
class to determine the service. A complete listing of available Bluetooth service classes
is referenced on the Bluetooth SIG web site.

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Default:

0000

Example: SC,0002

2.2.5// Set service class to 0002

SD,<value>

This command sets the class of device (COD) LSW. The COD is a 24-bit number thatis made up of the device class with major 8 bit and minor in a 16-bit word. This command is used with the service class command.
Default:

1F00

Example: SD,8040
To set the COD to 0x1F0123, use the following commands:
SC,001F
SD,0123

2.2.6

SE,<value>

In firmware versions 5.40, 6.10, and above, this command sets the UUID for outboundconnections. Roving Networks bluetooth modules use the standard SPP UUID of
0x1101. Encryption is always enabled in firmware versions 5.40 and higher.
2.2.6.1

FIRMWARE VERSION 5.40 & HIGHERThe UUID setting is useful for Android-based applications so that the application canuniquely determine the remote device. Android applications require a 128-bit UUID.
00001101-0000-1000-8000-00805F9B34FB is the 16-bit UMUID for the serial port profile (0x1101) when promoted to a 128-bit UUID. Android application developers are
expected to use this 128-bit UUID for SPP.
This feature applies to SPP connect back only, which is used primarily for Android
devices. With this feature, you can set a custom UUID for connecting back. Android
phones run an audio gateway that always attempts to grab a connection when it comesin from a remote Bluetooth device such as the Roving Networks module. With the SE
command, you can register a custom UUID, which ensures that ONLY your application
obtains the connection when it comes in.
The default SSP UUID is 35111C0000110100001000800000805F9B34FB.
You can modify a subset of the UUID; the bytes are changed from left to right. For
example, if the UUID is:35111C0000110100001000800000805F9B34FB
Typing the command SE,ABCD<cr> changes the first 2 bytes resulting in:
ABCD1C0000110100001000800000805F9B34FB
The command has three short forms:
SE,S// Loads the default SPP UUID

SE,I// Loads the iPhone UUID

SE,C// Loads the custom UUID (appropriate for testing or custom use)

spp_uuid[19] ={0x35,0x11,0x1C,0x00,0x00,0x11,0x01,0x00,0x00,0x10,0x00,0x80,0x00,0x00,0x80,0
x5F,0x9B,0x34,0xFB };www.rovingnetworks.com

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iphone_uuid[19] ={0x35,0x11,0x1C,0x00,0x00,0x00,0x00,0xDE,0xCA,0xFA,0xDE,0xDE,0xCA,0xDE,0x
AF,0xDE,0xCA,0xCA,0xFE };Where FE is the iPhone UUID and FF is a local UUID.
droid_uuid[19] ={0x35,0x11,0x1C,0xEE,0x28,0x6E,0xA0,0x00,0x01,0x11,0xE1,0xBE,0x50,0x08,0x00,
0x20,0x0C,0x9A,0x66 };Default:

0x1101

Example: SE,0000110100001000800000805F9B34FB // Set the UUID for Droid
2.2.6.2

FIRMWARE PRIOR TO VERSION 5.40

For firmware prior to version 5.40, the SE command enables and disables encryption.The <flag> value determines whether or not encryption is enabled as shown in
Table 2-4.
TABLE 2-5:
SET ENCRYPTION ENABLE
Flag

2.2.7

Description

0

Disable.

1

Enable.

SF,1This command restores the device to the factory defaults.
Example: SF,1

2.2.8// Restore factory defaults

SH,<value>

The HID flag register is a bit-mapped register that is configured while in commandmode. To set the register, use the SH, <value> command, where <value> is a 4-character hex word. The GH command returns the current value of the register. The default
factory setting is 0000, which corresponds to a keyboard.
Note:

This command is only available for use in the HID profile. Refer to Chapter
5. “HID Profile” for more information on using the HID profile.

Table 2-6 shows the HID flag register bits; currently only the lower 9 bits are defined.
See “HID Flag Register” on page 61 for more information on setting these bits.
TABLE 2-6:

HID FLAG REGISTER BITS

98Force HID mode if
GPIO11 is high on
power-up.

Toggle virtual keyboard on iOS when
first connected.

Default:

7..4
Descriptor type:0000 = Keyboard
0001 = Game Pad
0010 = Mouse
0011 = COMBO
0100 = JOYSTICK
1XXX = Reserved

2..0

Send output reports
over UART.

Indicates number ofpaired devices to which
the module can reconnect.

0200

Example: SH,0220
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3// Set the device as a mouse
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2.2.9

SI,<hex value>

The inquiry scan window command sets the length of time the device spends enablingan inquiry scan (discoverability). The minimum value is 0x0012, corresponding to about
a 1% duty cycle.
The page scan interval is fixed at 0x1000. The default window is 0x0100. The maximum
value is 0x800. Set this parameter to 0x0000 to disable inquiry scanning and render thedevice undiscoverable. If the host has already paired, the inquiry scan is not used.
Note:

Default:

When pairing with Android devices, increasing this value makes pairing
more reliable.
0100

Example: SI,0200

2.2.10// Set inquiry scan window to 0x0200

SJ,<hex value>

The page scan window command sets the amount of time the device spends enabling
page scanning (connectability). The minimum value is 0x0012, which corresponds toabout a 1% duty cycle. The page scan interval is fixed at 0x1000. The default window
is 0x0100. The maximum value is 0x800. Set this option to 0x0000 to disable pagescanning and render the device non-connectable.
Note:

Default:

When pairing with Android devices, increasing this value makes pairing
more reliable.
0100

Example: SJ,0200

2.2.11// Set the page scan window to 0x0200

SL,<char>This command sets the UART parity, where <char> is a character shown in Table 2-7.
TABLE 2-7:
UART PARITY VALUES
Value

Default:

E

Even.

O

Odd.

N

None.

N
// Set parity to even

Example: SL,E

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Description

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2.2.12

SM,<value>

This command sets the mode, where <value> is a decimal number as shown in
Table 2-8.
TABLE 2-8:
MODE VALUES
Value

Default:

Description

0

Slave Mode.

1

Master Mode.

2

Trigger Mode.

3

Auto-Connect Master Mode.

4

Auto-Connect DTR Mode.

5

Auto-Connect Any Mode.

6

Pairing Mode.

04

Example: SM,02.2.13// Set the mode to slave

SN,<string>This command sets the device name, where <string> is up to 20 alphanumeric characters.
Default:

N/A

Example: SN,MyDevice

2.2.14// Set the device name to “MyDevice”

SO,<string>This command sets the extended status string, where <string> is up to 8 alphanumericcharacters. Setting this string to from 1 to 8 characters permits status messages to besent to the local serial port. When you set this parameter, two status messages aresent:• When a Bluetooth connection is established, the device sends the string<string>CONNECT.
• When disconnecting, the device sends the string <string>DISCONNECT.
This parameter is useful when connecting to equipment or hardware. For example,
when the device is connected to a printer, the printer can examine an escapesequence. If <string> is set to ESC%, the printer can parse ESC%CONNECT and ESC%DISCONNECT messages without interfering with normal print jobs. In trigger or mastermodes, the first character of this string is used as the break connection character.
Default:

Disabled

Example: SO,ESC%
SO,<space>www.rovingnetworks.com// Set escape sequence// Disables the extended status string

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2.2.15

SP,<string>This command sets the security pin code, where <string> is up to 20 alphanumericcharacters. Each time the device pairs successfully, it saves the Bluetooth address.
The device can store up to eight addresses on a first in first out basis. Using this command also erases all stored pairings. You can use the same value that is already set.
You cannot erase the pin code, however, you can overwrite the default pin code.
Default:

1234

Example: SP,0123

2.2.16// Set pin code to “0123”

SQ,<mask>

This command is for special configuration settings, where <mask> is a decimal number
as shown in Table 2-9.
TABLE 2-9:
SPECIAL CONFIGURATION SETTINGS VALUES
Mask

Description

0

Default. The device does not use any special configuration.

4

With this option set, the device does not read the GPIO3 and GPIO6 pin values on
power-up. This command is used when configuring GPIO3 and GPIO6 for a function
other than the default configuration. See “GPIO Commands” on page 37.

8

Disables discoverability at power up. Clear this setting with SQ,0. Use the W or Q,1
commands to enable discovery at runtime.

16

This option configures the firmware to optimize for low latency data transfers rather
than throughput.

128

This option causes the device to reboot after disconnect.

256

This option sets 2 stop bit mode on the UART.

Note:

Default:

If the module is unable to connect to the Bluetooth device for 15 to 30 seconds after disconnecting, try clearing the SQ, bit (i.e., use SQ,0).
0// Do not use special configuration

Example: SQ,128

2.2.17// Reboot after disconnect

SR,<hex value>

This command stores the remote address, where <hex value> is 12 hexadecimal digits(6 bytes) with no spaces or characters between digits. Additionally, this command takes
two special characters for the address parameter:• SR,Z erases any stored addresses.
• SR,I writes the last address observed using the inquiry command. This command
can be helpful when you only have one other device in range.
Note:

Default:

In firmware version 6.12, you must type the SR,Z command in uppercase
characters. If you type the command in lowercase characters, the module
returns ERR.
N/A

Example: SR,00A053112233

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2.2.18SS,<string>This command sets the service name, where <string> is from 1 to 20 alphanumericcharacters. This command is not supported in firmware version 6.x.
Default:

SPP

Example: SS,SerialPort

2.2.19// Service name set to “SerialPort”

ST,<value>

This command sets the remote configuration timer, where <value> is a decimal number
from 0 to 255 representing the time window (in seconds) to allow remote configuration
over Bluetooth after power up in Slave Mode. In all Master modes, the remote configuration timer is set to 0 (no remote configuration). In Trigger Master Mode, the configuration timer is used as an idle timer to break the connection after time expires with nocharacters received.
The module supports a fast data mode. In this mode, the module does not go into command mode even if it receives $$$. If you do not enter command mode within the configuration window set by the configuration timer, the module enters fast data mode.
This command has the special modes shown in Table 2-10.
TABLE 2-10: CONFIGURAION TIMER SETTINGS
Value (Decimal)0
1 - 252

Default:

Description
No remote configuration. No local configuration when connected.
Time in seconds from power up to allow configuration.

253

Continous configuration, local only.

254

Continous configuration, remote only.

255

Continous configuration, local and remote.

60

Example: ST,0// Disable remote configuration// Enable remote configuration forever

ST,2552.2.20SU,<value>

The set UART baud rate command sets the baud rate where <value> is 1200, 2400,
4800, 9600, 19.2, 28.8, 38.4, 57.6, 115K, 230K, 460K, or 921K. You only need to specify the first 2 characters of the desired baud rate.
Note:

Default:

After a factory reset, the device returns 0 when you issue the GU command,
however, the module communicates at 115K.
115,200

Example: SU,57

2.2.21// Set the baud rate to 57,600

SW,<value>

This command enables low-power Sniff mode, which allows extremely low-power operation. In the mode, the device goes into a deep sleep and wakes up every 625 μs x
<value> to send/receive data. For example, the SW,0050 setting (0x50 = 80, 80 x
625 μs = 50 ms) causes the module to enter low-power sleep and wake once every 50
ms to check for RF activity.
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This setting is useful for applications in which the device is connected and sending
data. Data is not lost; however, it may have a delay. See “Sniff Mode” on page 42 formore details on this mode and managing power.
Default:

0000// Disable Sniff mode

Example: SW,0050

2.2.22// Enable Sniff mode with interval time of// 50 ms

SX,<flag>The bonding command determines which connections the device accepts, where<flag> is a value shown in Table 2-11. If bonding is enabled, the device only accepts
connections from the device that matches the stored Bluetooth address register. You
can set the stored address register with the SR command or it can be set upon the firstdevice pairing.
TABLE 2-11: BONDING VALUES
Flag

Default:

Description

0

Disable.

1

Enable.

0

Example: SX,1

2.2.23// Enable bonding

SY,<hex value>

This command sets the module’s transmit power, where <hex value> represents thedesired power setting.
In August 2012, Roving Networks changed the power setting hex values. The new
power setting:• Uses the desired power value instead of an arbitrary value• Shifts the power range up to use the highest transmit power• Provides more evenly spaced linear power values.
Table 2-12 describes the SY, power settings for August 2012 and later.
TABLE 2-12: POWER SETTINGS (AUGUST 2012 AND LATER)
Hex

www.rovingnetworks.com

Power (dBM)

0010

16

000C

12

0008

8

0004

4

0000

0

FFFC

-4

FFF8

-8

FFF4

-12

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Table 2-13 describes the power settings for the SY, command prior to August 2012.
TABLE 2-13: POWER TABLE (BEFORE AUGUST 2012)

Default:

Hex

Power (dBM)

0004

12

0000

6

FFFC

2

FFF8

0

FFF4

-5

FFF0

-10

FFE8

-20

16
// Set the power to 12 dBM

Example: SY,000C

To determine which power settings your module uses, you restore your module to thefactory defaults and then view the power setting. The factory default is for the module
to use maximum power. Therefore, if the power setting displays as 10 hex (16 decimal),the module uses the new power settings. If the power displays as 4 hex (12 decimal),the module uses the old power settings.
To find the power setting:
1.
2.
3.
4.
5.

Type $$$ in a console to put the module into command mode.
Type SF,1 <cr> to restore the factory defaults.
Type R,1 <cr> to reboot the module.
Type $$$ to go into command mode.
Type GY <cr> to view the power setting.

2.2.24

SZ,<value>

You use this command to specify non-standard raw baud rates, where <value> is adecimal number based on the formula <value> = baud rate x 0.004096. This setting
takes effect after rebooting.
Default:

N/A

Example: SZ,39

www.rovingnetworks.com// Set the baud rate to 9,521.48

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2.2.25

S~,<value>

This command sets the profile, where <value> is shown in Table 2-14. See “Profile Settings & Features” on page 46 for more details on profiles.
TABLE 2-14: PROFILE VALUES
ValueProfileComments

0

SPP

Default, no modem control.

1

DUN-DCE

Slave or gateway. Note 1

2

DUN-DTE

Master or client. Note 1

3

MDM SPPWith modem control signals. Note 1, Note 2

4

SPP and DUN-DCE Multi-profile. Note 1

5

APLApple (iAP) profile. Refer to the iAP Bluetooth Evaluation Kit forDeveloping Accessories Compatible with iOS Devices User
Manual for more information on using this profile.

6

HID

HID profile. To use the Bluetooth HID profile, the device mustbe running a special firmware version. See Chapter 5. “HIDProfile” for more information.

Refer to “Profile Settings & Features” on page 46 for information onmodem control signals and GPIO assignments.

Note 1:In this mode, GPIO11 is reserved for RTS.

2:
Default:

0

Example: S~,02.2.26// Set profile to SPP

S-,<string>This command sets the serialized friendly name of the device, where <string> is up to
15 alphanumeric characters. This command automatically appends the last 2 bytes of
the Bluetooth MAC address to the name, which is useful for generating a custom namewith unique numbering.
Default:

N/A

Example: S-,MyDevice

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2.2.27

S?,<flag>The role switch command enables and disables the role switch, where <flag> is shownin Table 2-15. If the switch is set, when a slave mode device receives an incoming connection, the device tries to force a role switch, allowing the slave to become the master.
This option is useful in situations where the local device sends high-speed data up to
the remote host, and can result in better performance. However, this setting may createa situation in which the connecting host cannot make additional outbound connections(multi-point) while connected to this device.
TABLE 2-15: ROLE SWITCH VALUES
Flag

Default:

Description

0

Disable.

1

Enable.

0

Example: S?,1

2.2.28// Enable role switch

S$,<char>This command sets the configuration detect character string, where <char> is a single
character. This setting allows you to change the default string to go into commandmode ($$$) to some other character string. Restoring the factory defaults returns thedevice to using $$$.
Default:$

Example S$,#2.2.29// Set ### as string to go into command// modeS|,<value>

The low-power connect mode command disables the Bluetooth radio and LED timers
while not connected, where <value> is a 4-digit number made up of two 1-byte intervals. The first interval is the off period and the second the on period. Both are in hex
seconds (not decimal). The maximum value for either interval is 20 seconds. The
default is 0000, which indicates always actively waiting for a connection.
When this option is set, the module cycles between active (discoverable and connectable) and low-power deep sleep. This setting can save considerable power when themodule is waiting for a long time without a connection. The trade off is additional
latency when connecting or pairing.
Default:

0000

Example: S|,2001

www.rovingnetworks.com// Cycle on for 1 s and OFF for 32 s// (hex 20 = decimal 32)

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2.3

GET COMMANDS
The get commands retrieve and display the device’s stored information. These commands do not have a keyword or character and do not take any parameters, except as
noted.

2.3.1

DThis command displays basic settings such as the address, name, UART settings,
security, pin code, bonding, and remote address.
Example: D

2.3.2// Display basic settings

E

This command displays the device’s extended settings such as the service name, service class, device class, and configuration timer.
Example: E

2.3.3// Display extended settings

GB

This command returns the device’s Bluetooth address.
Example: GB

2.3.4// Display the device’s Bluetooth address

GF

This command returns the Bluetooth address of the currently connected device. This
command can give a different result than the GR command, which is the stored remoteaddress for re-connecting.
Example: GF

2.3.5// Show Bluetooth address of currently// connected device

GK

This command returns the device’s current connection status. 1,0,0 indicates thedevice is connected; 0,0,0 indicates that it is not connected.
Note:

If diagnostic messages are enabled (using the SO,% command) and thedevice is not connected, NO_AUTH_CHIP is displayed on the UART and themodule returns the error code 8 when you issue the GK command.

Example: GK

2.3.6// Show the current connection status

GR

This command shows the remote address.
Example: GR

2.3.7// Display remote address

G&

This command returns a hex byte containing the value of the GPIO pins.
Example: G&

www.rovingnetworks.com// Show the GPIO pin values.

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2.3.8

G<char>This command displays the stored settings for a set command, where <char> is a set
command name.
Example: GS

2.4// Return 1 or 0 depending on the security// value

CHANGE & ACTION COMMANDS
Change commands temporarily change the value of various settings such as serial
baud rate, parity, etc. Action commands perform actions such as inquiries, connecting,and entering/exiting command mode.

2.4.1

$$$

This command causes the device to enter command mode, displaying CMD. The device
passes characters as data until it sees this exact sequence. If the device sees any
bytes before or after the $$$ characters in a 1 second window, the device does notenter command mode and these bytes are passed through.
You can change the character string used to enter command mode with the S$ command.
Example: $$$2.4.2// Enter command mode---This command causes the device to exit command mode, displaying END.
Example: ---2.4.3// Exit command mode+This command toggles the local echo on and off. If you send the + command in command mode, all typed characters are echoed to the output. Typing + a second timeturns local echo off.
Default:

Off

Example: +2.4.4// Turn local echo on&

This command returns the evaluation kit’s dipswitch values or GPIO3, 4, 6, 7 values onother modules.
Example: &2.4.5// Display dipswitch or GPIO values

C

This command causes the device to attempt to connect to the stored remote address.
Example: C

www.rovingnetworks.com// Connect to stored remote address

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2.4.6

C,<address>

This command causes the device to connect to a remote address, where <address> is
specified in hex format. The address is also stored as the remote address.
Example: C,00A053112233

2.4.7// Connect to the Bluetooth address// 00A053112233

CF,<address>

This command causes the device to connect to <address> and immediately go into fast
data mode.
Note:

You cannot enter command mode while connected using this command.
However, GPIO6 can still be used to disconnect. Therefore, you should
hold GPIO6 high before sending this command because if GPIO6 goes low,the device disconnects.

Example: CF,00A053112233

2.4.8// Connect to 00A053112233 in fast data// mode

CFI

This command causes the device to connect and immediately go into fast data modeusing the last address found with the inquiry command.
Note:

You cannot enter command mode while connected using this command.
However, GPIO6 can still be used to disconnect. Therefore, you should
hold GPIO6 high before sending this command because if GPIO6 goes low,the device disconnects.

Example: CFI

2.4.9// Connect to last found address in fast// data mode

CFR

This command causes the device to connect and immediately go into fast data modeusing the stored remote address. This command is similar to the C command, except it
bypasses the configuration timer.
Note:

2.4.10You cannot enter command mode while connected using this command.
However, GPIO6 can still be used to disconnect. Therefore, you should
hold GPIO6 high before sending this command because if GPIO6 goes low,the device disconnects.

CT,<address>,<value>

This command uses a timer to control the connection duration, where <address> is theconnection address (required) and <value> is the length of the timer in ¼ seconds up
to 255 (optional). For example, a <value> of 255 is 64 seconds.
The device does not use or store a remote address. The device automatically disconnects after 7 seconds if no data is seen from the UART or over Bluetooth. You can use
the optional timer <value> to change the timer length.

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Example: CT,00A053112233

CT,00A053112233,120

2.4.11// Connect to 00A053112233 and// disconnect after 7 seconds if// no data is seen from UART or Bluetooth// Connect to 00A053112233 and// disconnect after 30 seconds if// no data is seen from UART or Bluetooth

F,1This command ends configuration immediately and puts the device into fast data mode.
Example: F,1

2.4.12// Leave command mode and enter fast// data modeH

The help command displays a list of commands and their basic syntax.
Example: H

2.4.13// Display help

I,<value 1>,<value 2>This command performs an inquiry scan, where <value 1> is the scan time in seconds
and <value 2> is the optional COD of the device class for which you are scanning. The
default time is 10 seconds, and the maximum is 48. If <value 2> is unused or set to 0,
the device looks for all device classes. When entering a COD, you must provide all six
characters, e.g., you would enter 0040F0 for COD 0x40F0. The scan returns a maximum of 9 devices. As devices are found, they are displayed in the format:<Bluetooth address>,< Bluetooth name>,<COD>00A053000123,MySerialPort,72010C
Default:

10 seconds, no COD

Example: I,20,0040F0

2.4.14// Scan for 20 seconds using the COD// 0x40F0

IN<value 1>,< value 2>This command is similar to the I command, but it does not return the Bluetooth name,where <value 1> is the scan time in seconds and <value 2> is the optional COD of thedevice class for which you are scanning. Therefore, the device returns the scan resultmuch faster because the device does not have to perform a remote lookup for eachdevice found.
Example: IN10,001F00

2.4.15// Scan for 10 seconds using the COD// 0x1F00

IQ

This command scans for Bluetooth devices in pairing mode and returns the RSSI,
which is an indicator of the signal quality for remote devices. Inquiry scaning with RSSI
is part of the Bluetooth specification where the Tx power is held a constant level (nopower control) while sampling the RSSI. A useful application for RSSI scanning is proximity based pairing.
Example: IQ

www.rovingnetworks.com// Scan for devices and return their RSSI

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2.4.16

IS<value>

This command performs an inquiry scan with a COD of 0x001F00, which is the default
COD for Roving Networks modules, where <value> is the scan time in seconds.
Example: IS10

2.4.17// Scan for Roving Networks devices for// 10 seconds

IR<value>

This command performs an inquiry scan with a COD of 0x0055AA, where <value> isthe scan time in seconds. Roving Networks modules use this COD for instant cablereplacement.
Example: IR10

2.4.18// Scan for instant cable replacement// devices for 10 seconds

J

This command hides the current 4-digit pin code (or pairing code) used for legacy pairing mode or default mode. When the pin code is hidden, the GP, D, and X commands
do NOT display the currently assigned pin code.
To disable the pin code hiding:• Use the SP, command to set a new pin codeor
• Restore the factory defaults using the commands
SF,1
R,1

Example: J

2.4.19// Hide the pin codeK,

The kill command disconnects the device the current connection. The characters
KILL<cr><lf> are echoed to the local UART once the connection is broken.
Example: K,

2.4.20// Disconnect the current connection.

L

The link quality command returns the real-time streaming link quality values at 5 Hz.
The returned value is two bytes separated by a comma, where ff is the highest value.
The first byte is the current reading and the second byte is the low water mark. Example
output for RSSI is ff,e6.
If the module is not connected, the module responds with NOT Connected! when you
issue the L command.
Example: L

2.4.21// Display the real-time streaming link// quality value

M

This command displays the remote side modem signal status.
Example: M

www.rovingnetworks.com// Show the remote side modem signal// status

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2.4.22OThis command displays other settings, such as the configuration character, I/O port values, and debug mode.
Example: O

2.4.23// Show the other settings

P,<char>This command passes through any <char> up to a carriage return or line feed while incommand mode.

2.4.24

Q

This command puts the device into quiet mode, which means it is temporarily not discoverable or connectable. When you issue this command, the device responds Quiet.
This command does not survive a power cycle or reset.
You use this command with the Z command. For the lowest power mode, issue Q andthen Z. Use the Sniff settings for the lowest power while connected. See “Power Management” on page 41 for more details on low-power mode.
In firmware version 6.15 and higher, the Q command has the following settings thathave different responses as follows:• Q—The module is undiscoverable (firmware version 4.77 and 6.15 and higher).
• Q,0—The module is discoverable and able to connect. Response is AOK. (firmware 6.11 and higher)• Q,1—The module is not discoverable and not able to connect. (firmware version
6.11 and higher)• Q,2—The module is able to connect but is not discoverable. (firmware version
6.11 and higher)• Q,?—Displays the current quiet mode where ? is 0, 1, or 2 as defined above (firmware version 6.15 and higher).
Note:

2.4.25In firmware version 6.11 and 6.12, the Q command displays the quiet mode.

R,1This command forces a complete device reboot (similar to a power cycle).
Note:

2.4.26

Any changes to the device configuration using the set commands will nottake effect until you reboot the device.

T,<flag>

This command passes received data (from the UART or Bluetooth) while in commandmode according to the <flag> value shown in Table 2-16.
TABLE 2-16: T COMMAND VALUES
Flag

Description

0

Disable.

1

Enable.

Example: T,1

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2.4.27

U,<value 1>,<value 2>This command causes a temporary UART change, where <value 1> is the baud rateand <value 2> is the parity. This command changes the serial parameters immediately,
but does not store them to flash memory. The device returns AOK at the current settings,
then automatically exits command mode and switches to the new baud rate.
The baud rate, <value 1>, must be EXACTLY 4 characters: 1200, 2400, 4800, 9600,
19.2K, 38.4K, 57.6K, 115K, 230K, 460K, or 921K. The parity, <value 2>, is E, O, or N
(must be capital letters).
Default:

60

Example: U,9600,E

2.4.28// Set the baud rate to 9,600 with even// parity

V

This command displays the firmware version.
Example: V

2.4.29// Show the firmware version

W

This command enables discovery and connection after it has been disabled with the Q
command. It reloads the stored value of the inquiry and page window to re-enable. The
device returns Wake as a response.
Note:

For backwards compatibility with firmware version 4.77, this command isavailable in firmware version 6.15 and higher.
In firmware version 6.11, the W command is deprecated. Instead, use Q,1.

Example: SI,0000// Turn off discovery but still allow// connections// Turn on discovery and connections

W

2.4.30Z

When you use this command, the device enters low-power, deep sleep mode (<2 mA)
when NOT connected. To exit this mode, power cycle the device or toggle the module’s
reset pin (causing a hard reset). For more information on managing power, see “PowerManagement” on page 41.

2.5

GPIO COMMANDSGPIO commands configure and manipulate the module’s GPIO signals. Each GPIO
command takes a 16-bit parameter made up of 2 bytes. The first byte is a mask to specify the GPIO number and the second byte is the command’s value:
PARAMETER[15:0] =2.5.1

MASK[7...0]<<8 ||VALUE[7..0]

S@,<hex value>

This command sets the GPIO pin’s direction (input or output). This setting is lost whenpower is cycled.

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2.5.2

S&,<hex value>

This command sets the GPIO pin’s value. This setting is lost when power is cycled.

2.5.3

S%,<hex value>

This command stores the GPIO pin’s direction for use on power up.

2.5.4

S^,<hex value>

This command stores the GPIO pin’s powerup value.

2.5.5

S*,<hex value>

This command sets values for GPIO8, GPIO9, GPIO10, and GPIO11.

2.5.6

Controlling the GPIO Pins

Two registers control the GPIO pins:• The direction register controls whether the GPIO is an input or an output.
• The second register is the value to apply to the GPIO if it is an output, or it is thevalue of the built-in, weak pull-up resistor if the GPIO is an input.
These settings are immediate and do not survive a power cycle.
Example: S@,8080

2.5.7// Set GPIO7 as an output

S&,8080// Drives GPIO7 highS&,8000// Drives GPIO7 low

Setting GPIO Pin Power-Up Values

There are two additional registers that control the GPIO pin direction and value on
power up. You set these registers with the S% and S^ commands.
Example: S%,0101// Set GPIO0 as an output on power-up

S^,0303// Drive GPIO0 high and pull up GPIO1

You can set multiple bits can be set with a single command. Any bits with a mask of 0
are unaffected.
Some GPIO pins are read at power-up to perform certain functions; therefore, you must
be careful when manipulating them. For example, you can use GPIO3 and GPIO6 to
set master mode and auto discovery automatically. If you want to use these GPIO pinsfor other purposes at power-up, you must disable the module from sensing these GPIO
pins upon power-up by using the SQ,4 command. This command sets a flag in a stored
register that is read at power-up. View the GPIO pin’s power-up settings using the O(other settings) command.

WARNING
GPIO4 is used by the system to reset stored parameters to factory defaults. If GPIO4
is pulled high on power-up and then toggled 3 times, all user settings returns to thefactory default values. Therefore, you should not use this pin as an output and yoursystem should not drive it high at power-up (first 1 second of operation).

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GPIO2 and GPIO5 are driven by the embedded software as outputs. You can disable
them using the direction command (for example to save power) and them use them as
inputs. If these pins are set as outputs the software overrides any user values.

2.5.8

Setting GPIO8, GPIO9, GPIO10 & GPIO11

You use the S*, command to set these GPIO pins:
S*,<hex value> = MASK[11..8] VALUE[11..8]

For the upper 4 GPIO pins, a single word controls the mask and values,. Only the lower
4 bits of each byte are used. The first time you use this command, all 4 GPIO pins are
driven as outputs and remain as outputs until a power cycle. These bits cannot be set
to be read on powerup. Some modules do not offer these GPIO pins.

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Chapter 3. Advanced Topics
This section provides information on advanced topics such as power management,
profile settings, design concerns, etc.

3.1

POWER MANAGEMENT
There are five different methods to lower Bluetooth device power consumption. Somemethods only have an effect when the device is in certain Bluetooth states (i.e., whenconnected or disconnected). Additionally, each method has advantages, disadvantages, and requirements. Table 3-1 summarizes these methods.

TABLE 3-1:

POWER MANAGEMENT METHODS

MethodBluetooth State

Advantages

Disadvantages

Optimize Inquiry(Discovery) andPage (Connection)
Window

Idle (Not Connected) or Active
Connection

The current can be reduced from more
Causes additional latency
than 20 mA to less than 5 mA (combining when pairing or connecting.
this method with Sniff mode uses lessthan 3 mA).

Sniff Mode

Transmit
Active Connection

This mode can be combined with the
Optimize Inquiry (Discovery) and Page
(Connection) Window or Enable Deep
Sleep methods for lower power consumption.

-

Enable Deep Sleep

Idle (Not Connected)

With this method, current is reduced toabout 300 μA.

This method can cause
latency issues and may drop
the first byte if the device
wakes on RX data. It also
causes a loss of performance/power when thedevice wakes frequently.

Disable Output Driv- Idle (Not Coners
nected) or Active
Connection

This method is simple to use. However, it External components driven
depends on the load: if the device is not by GPIO pins may not work
connected there are no power savings.
properly.
This method is required for Roving Networks evaluation boards to measure
power accurately.

Lower Transmit
PowerThis method lowers power consumption The device has a shorter
during Txmt and active mode by reducing effective range.
radio output power.

Idle (Not Connected) or Active
Connection

3.1.1

Optimizing Inquiry (Discovery) & Page (Connection) Windows

In slave mode, there are two timers that can be used to lower radio power radio while
idle. When not connected, the Bluetooth radio is active when listening for other devices.
Other devices can discover (inquire) or connect (page) to the device. The amount oftime the radio listens is called the window, and the interval at which the process repeats
is called the interval.
For Roving Networks devices, the inquiry and page window is fixed at is 0x1000(2.56 seconds). The default window is 0x0100 (160 ms) or a 6.25% duty cycle. By lowering the window values, you can save power at the expense of possibly missing an
inquiry or page request. Because the host usually retries many times automatically, theonly downside is a delay in discovery or connection time.
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You adjust the inquiry scan window using the SI command. The minimum window forinquiry or page is 0x0012 (11.25 ms), which corresponds to about a 0.5% duty cycle.
Example: SI,0200// Set the inquiry scan window to 0x0200

You adjust the page scan window using the SJ command. The minimum window forinquiry or page is 0x0012 (11.25 ms), which corresponds to about a 0.5% duty cycle.
Example: SJ,0200// Set the page scan window to 0x0200

Thus, you can reduce the average power from more than 20 mA to less than 5 mA instandard mode and less than 3 mA in Sniff mode.
It is also possible (and desirable for security reasons) to completely disable inquiry.
Once a host has found and installed a device, inquiry is not required, only page is used
to make a connection. To disable inquiry while still allowing connections, set the inquiry
timer to 0 with the SI,0000 command.

3.1.2

Sniff Mode

Sniff mode, a Bluetooth power conservation method, only pertains to an active connection. In Roving Networks devices, Sniff mode is disabled by default and the radio is
active continuously when connected (about 25 to 30 mA). In Sniff mode, the radio
wakes up at specific intervals and sleeps in very low power mode (around 2 mA) the
rest of the time. With Sniff mode, the power savings can be quite dramatic.
To enable Sniff mode, use the SW,<hex value> command. Example interval timers:
0x0020 = 20 ms (32 decimal * .625 = 20)
0x0050 = 50 ms
0x00A0 = 100 ms
0x0190 = 250 ms
0x0320 = 500 ms
0x0640 = 1 second
When a connection is made, both master and slave must support Sniff mode and agree
to the Sniff window, otherwise, the radio remains in full active mode.
Note:

3.1.3

The maximum allowed Sniff interval is about 20 seconds, which is 0x7FFF.

Enabling Deep Sleep

You can use deep sleep mode to obtain extremely low power operation. In this mode,the device shuts down completely and only draws about 300 μA of current. To enable
deep sleep, set the high-order bit of the Sniff word to 0x8000. This bit is NOT used todetermine the sleep interval, it is only used as a flag to enable deep sleep.
Example: SW,8320// ½ second sleep (0x0320), with deep// sleep enabled

In normal low-power sleep (not deep sleep) the firmware is still running in idle mode,
and wakes up about 20 times per second to check ports, update LEDs, etc. During
deep sleep, the firmware actually stops running some tasks. For example, the LEDs
only update about once per second. There are 3 ways to wake the radio from sleep
mode:• Send a character to the UART.
• Transition the RX pin. The worst-case wake time is 5 ms. Therefore, the radio
generally loses the first character sent. A better way to wake the radio is to toggle
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the CTS line from low to high, wait 5 ms, and then send data.
• The radio can wake automatically every <hex value> slot times (1 slot time is
625 μs) as defined previously. The radio wakes and listens to see if the other sideof the connection has anything to send. This wake time is typically about 5 ms (8slots) even if no data is to be transferred.
Once the radio is awake it stays active for exactly 1 second of inactivity, and then sleeps
again.
Note:

Setting this mode can cause latency issues and dropped bytes/loss of performance in cases where large amounts of data are being transferred. The
nuances of Bluetooth Sniff can be complex. If necessary, contact Roving
Networks for more details on how to use Sniff mode.

To enable even lower power utilization, use the S|,<hex value> command to set anon/off duty cycle.

3.1.4

Disabling Output Drivers

Use the S%,1000 command to set all GPIO pins (0 to 11) to inputs. This command also
turns off the FireFly adapter LED (GPIO5). Refer to “GPIO Commands” on page 37 formore information on using commands to control the GPIO pins.

3.1.5

Lowering Transmit PowerAll Roving Networks Bluetooth modules adhere to the Bluetooth (version 1.1, 1.2, and
2.0/2.1) specifications for power control. The RN-21 and RN-41 radios are Class 1
capable.
The radio power output is automatically controlled by the baseband. Depending on themode (inquiry scan, page scan, connected) the power is adjusted. Once a connection
is made, the radios on both sides negotiate a power setting based on the perceived signal strength (RSSI).
The transmit power can be controlled to:• Reduce effective range for security reasons.
• Lower radio emissions for agency compliancy concerns.
• Reduce total power consumption.
To configure the transmit power, use the SY,<hex value> command, where <hex
value> is an unsigned hex representation of the setting command. See Table 3-2. The
radio can use a value that is lower than the default.
TABLE 3-2:
POWER SETTINGS
Hex

www.rovingnetworks.com

Power (dBM)0010

16 (default)

000c

12

0008

8

0004

4

0000

0

FFFC

-4

FFF8

-8

FFF4

-12

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If a non-zero value is stored in the variable, upon power up the radio uses the highest
value that is less than or equal to the stored variable.
Example: SY,FFF8// -8 dBM// 0 dBm

SY,0000

The power setting takes effect after a power cycle, reboot, or reset pin toggle. To checkthe stored power setting, use the O command; the device returns TX Power=1 (or othersetting equal to the value you entered). To view the current power setting, use the GY
command. The device returns only the actual value with no leading zeroes. The GY
value may not match the value in the shown with the O command due to how the value
is used as described previously.
Note:

3.2

Prior to August 2012, the SY, command used different power settings.
Refer to “SY,<hex value>” on page 27 for more information on the oldpower settings and to determine which power settings your module uses.

CONFIGURATION TIMER SETTINGS
The module has a remote configuration timer to allow remote configuration over Bluetooth after power up in Slave Mode. In all Master modes, the remote configuration timer
is set to 0 (no remote configuration). In Trigger Master Mode, the configuration timer isused as an idle timer to break the connection after time expires with no characters
received.
You can only configure remotely if the boot-up configuration timer (default 60 seconds)
has not expired. This timer is set to 0 (remote configuration disabled) for Master Modeand Auto-Connect Slave Mode so that data can immediately flow between 2 modules
for cable replacement applications. Once the timer has expired, any data sent to themodule passes through unmodified and unrecognized by the command interpreter. The
timer can be set to any value from 0 (disable remote configuration) to 255 decimal,
which allows continuous (no timeout) configuration.
Table 3-3 shows the configuration timer settings.
TABLE 3-3:
CONFIGURATION TIMER SETTINGS
Value(Decimal)0

Description
No remote configuration. No local configuration when connected.

1 - 252

Time in seconds from power up to allow configuration.

253

Continous configuration, local only.

254

Continous configuration, remote only.

255

Continous configuration, local and remote.

You use the ST,<value> command to change the configuration timer settings. For
example:ST,0
ST,255www.rovingnetworks.com// Disable remote configuration// Enable remote configuration forever

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3.3

INTERFACING TO A MICROPROCESSOR
Roving Networks Bluetooth devices can connect to 3.3-V (only) microprocessors using
the UART interface. When interfacing with a microprocessor, use the following guidelines:• The Bluetooth device power, ground, RX, and TX signals must be connected andCTS should be held low or tied to RTS.
• The Bluetooth device can go into command mode 500 ms after booting.
• The microprocessor should send $$$ with no carriage return or line feed to entercommand mode.
3.3.0.1

HOW DO I KNOW THE MODULE IS READY FOR COMMAND MODE?

500 ms after rebooting, the module is ready for command mode. You send $$$with nocarriage return.
3.3.0.2

WHICH HARD SIGNALS SHOULD I CONNECT?

You should connect power, ground, RX, and TX. CTS should be low or you can connect
or tie it to RTS.

3.4

HCI MODE
Roving Networks offers the Host Controller Interface (HCI) mode in addition to the standard operational mode of its Bluetooth modules (standard mode refers to the on-board
stack running on the module).
In HCI mode, the on-board stack is bypassed and the module is put in a state that runs
the Bluetooth baseband. The HCI provides a command reference interface to the baseband controller and the link manager, and provides access to the hardware status andcontrol registers. This interface provides a uniform method for accessing the Bluetooth
baseband capabilities.
In this mode, the Bluetooth stack is no longer on-board the module. It is offloaded tothe interfacing host processor. The Bluetooth module is used as a radio, performing thelower level MAC functionalities, while the application stack runs on the host processor.
Using the module in HCI mode allows designers to implement profiles that are notnatively supported on the Bluetooth module.
Note:

HCI mode requires a separate firmware build that must be loaded into themodule’s flash at the factory. It cannot be updated in the field or by the user.

Roving Networks offers HCI mode in two hardware interfaces:• HCI over UART• HCI over USB

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3.4.1

HCI over UARTIn this mode, the hardware interface between the host processor and the Bluetoothmodule is the UART. You must interface the flow control signals between the host processor and the Bluetooth module for the HCI interface to work. Failure to do so cancause the host processor and the Bluetooth module to become out of sync and breakthe Bluetooth link.

3.4.2

HCI over USB

In this mode, the hardware interface between the host processor and the Bluetoothmodule is the USB. In this architecture, the Bluetooth module is the USB slave and thehost processor is the USB host.
Using the USB interface offers the advantage of a faster data link between the Bluetooth module and the host processor. With this architecture, it is possible to achieve
Bluetooth’s theoretical maximum throughput of 3 Mpbs.

3.5

PROFILE SETTINGS & FEATURES
The default profile for Roving Networks Bluetooth device is the Serial Port Profile(SPP). However, the firmware also supports the DUN profile in both master and slavemodes. To change the profile, use the S~,<value> command, where <value> is shownin Table 3-4. Refer to “HID Profile” on page 59 for more information on using HID.
TABLE 3-4:
PROFILE CHANGE VALUES
ValueProfileComments

0

SPP

Default, no modem control

1

DUN-DCE

Slave or gateway

2

DUN-DTE

Master or client

3

MDM SPPWith modem control signals

4

SPP and DUN-DCE

Multi-profile

5

APL

iAP data connection to iOS device

6

HID

Human interface device (keyboard, mouse, etc.)

The most common use of DUN profile is to allow a Bluetooth client to connect to a
dialup modem. For this mode, use profile 1 (DUN-DCE) or S~,1. You may also want to
set the COD so that clients can recognize the device as a Bluetooth modem (COD
0x040210) using the following commands:
SC,0004
SD,0210
With firmware version 4.74 and higher, the device can connect to either SPP or DUN(but not both at the same time). When a host discovers the device, the device displays
both services. The host can connect to either one. The device can also connect using
the SPP profile, disconnect, and then connect using the DUN profile.

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3.6

USING GPIO PINS AS MODEM CONTROL SIGNALSRNXX modules can replicate the required modem control hardware signals automatically once a connection is made. These signals are transferred outside the data channel (using RFCOMM control channels) and are automatically updated. The default SPP
profile (profile = 0) does not drive these signals or report back inputs. If DUN or MDM
profiles are enabled (profile = 1, 2, or 3), the following signals are automatically driven
and received:• Inputs, active low. These signals are read and sent back over Bluetooth to theremote host.
- GPIO3 = DCD (dipswitch 2)- GPIO6 = DSR (dipswitch 3)- GPIO7 = CTS (dipswitch 4)• Outputs. The remote host sends these signals and drives them out.
- GPIO10 = DTR (active high)- GPIO11 = RTS (active low)On the Firefly module, you can also use the dipswitches to set/clear the DCD, CTS, andDSR signals. The DTR and RTS signals are available on the 9-pin header as well.

3.7

DESIGN CONCERNSThis section provides information on design concerns, such as hardware signals, hardware connections and power, LED status, optimizing for latency and throughput, common problems, etc.

3.7.1

Hardware Signals

The following sections provide information on the reset circuit, factory reset, connection
status, SPI bus, and other hardware connections.
3.7.1.1

RESET CIRCUITThe RN41/RN42 modules contain a 1k pull-up to VCC, and the reset polarity is active
low. RN21/RN22 modules contain a 1k pull-down, and the reset polarity is active high.
The module’s reset pin has an optional power-on-reset circuit with a delay, whichshould only be required if the input power supply has a very slow ramp or tends tobounce or have instability on power up. Often a microcontroller or embedded CPU I/O
is available to generate the reset once power is stable. If not, designers can use one of
the many low-cost power supervisor chips currently available, such as the MCP809,
MCP102/121, and Torex XC61F.
3.7.1.2

FACTORY RESET GPIO4

Roving Networks recommends that designers connect the GPIO4 pin to a dipswitch,jumper, or resistor so that it can be accessed. This pin can be used to reset the module
to its factory default settings, which is critical in situations where the module has been
misconfigured. To reset the module to the factory defaults, GPIO4 should be high on
power-up and then toggle low, high, low, high with a 1 second wait between the transitions.

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3.7.1.3

CONNECTION STATUS

GPIO5 is available to drive an LED, and it blinks at various speeds to indicate status(see Table 3-5). GPIO2 is an output that directly reflects the connection state as shownin Table 3-6.
TABLE 3-5:
GPIO5 STATUS
GPIO5 Status

Description

Toggle at 1 Hz

The module is discoverable and waiting for a connection.

Toggle at 10 Hz

The module is in command mode.

Low

The module is connected to another device over Bluetooth.

TABLE 3-6:

GPIO2 STATUS

GPIO2 Status

DescriptionHigh

The module is connected to another device over Bluetooth.

Low

The module is not connected over Bluetooth.

3.7.1.4

USING THE SPI BUS FOR FLASH UPGRADES

While not required, this bus is very useful for configuring the Bluetooth modules’
advanced parameters. The bus is required when upgrading the module’s firmware. Ina typical application, a 6-pin header can be implemented to gain access to this bus. A
minimum-mode version might simply use the SPI signals (4 pins) and obtain groundand VCC from elsewhere in the design.
3.7.1.5

HARDWARE CONNECTIONS & POWER

When designing with Roving Networks Bluetooth devices, follow these guidelines:• Placing 3.3-V DC power into the GPIO pins while they are set up as outputs will
permanently damage the radio modules. The failure mode is short across GND
and VCC. Use a 10-KΩ resistor in series or a 10-KΩ pull-up resistor for input andoutput GPIO pins, respectively.
• Do not leave any GPIO pins floating (or have LEDs that might drift up to a voltage
such as 1.8 V) because it causes leakage in low-power mode.
• By default, you drive CTS high to enable deep sleep and then wake the device bypulling CTS low. However, in some cases, you may need to tie the CTS pin high
(3.3-V inactive) for the module to go into deep sleep. This change must be performed at the factory; contact Roving Networks for more information.
• Connect a common ground when using the external TX/RX inputs 0 – 3.3 V DC.
• For a 3-wire DB-9 interface (TX, RX, and GND only), connect/short CTS to RTS.
The factory default is hardware flow control enabled, and CTS and RTS connected.
• When using a 5.0-V DC input, GPIO pins require a voltage divider. A good choice
is a 10 KΩ series with 20 K to ground. The GPIO pins are 0 - 3.3 V DC, not 5-V tolerant.
• To obtain the lowest power, the device should be passive (in slave mode and not

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trying to make any connections). When sleeping, the device uses 26 μA.
Note:

To connect with Android phones, the module must wake up once in a whileand be connectable (in this mode, the radio draws about 25 mA). The minimum wakeup time is 11 ms every 2.5 seconds, which gives an average
power of about 200 μA to be able to connect. You can fine-tune the powerusage by and turning the radio off for a number of seconds, e.g., 20 seconds, which draws 26 μA.

• Hardware communications connections for modules and evaluation board- Radio TX Æ RX of the application microcontroller unit (MCU)- Radio RX Å TX of the application MCU- Radio RTS Æ CTS of the application MCU- Radio CTS Å RTS of the application MCU

3.7.2

LED Status

Table 3-7 describes the green LED status. If installed on the evaluation board or module, the yellow LED blinks when data is transferred on the DB9 serial port’s RX or TX
pins. This LED is a physical monitor of the actual voltage, and is not driven by softwarein the module. If installed, the blue LED indicates the transmit activity on the Bluetooth
link over the air interface.
TABLE 3-7:
GREEN LED STATUS
Mode

Green LED Blink Rate

Configuring

10 times per second

Startup/Configuration Timer

2 times per second

Discoverable/Inquiring/Idle

Once per second

Connected

Solid On

3.7.3

Optimizing for Latency or Throughput

The firmware must make decisions automatically on when to forward received data
coming into the UART RX input out the RF link. By default, the firmware is optimized
for throughput. In some cases, especially with smaller, close-spaced incoming data
packets, the data can get split, with a partial packet forwarded and other data coming
later. Unfortunately, Bluetooth has algorithms that can cause significant latency
between packets (> 10 ms) at certain times. If the host protocol expects data to comeas contiguous bursts and has short timeouts, this latency can cause errors.
Another optimization method forces the radio to attempt to keep small bursts of data
together. In this mode, the firmware is optimized for latency. To enable this mode, use
the special debug command SQ,16, which sets the latency bit in the firmware. To disable this mode, use the SQ,0 command. You can read the register’s value with the GQ
command.
Note:

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This command gives a result in hex even though the command is set in decimal.

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3.7.4

Limitations of 7-Bit Data Mode

Roving Networks firmware supports a selectable 7-bit data mode using the S7,1 command. The Bluetooth hardware, however, does not support 7-bit data, so this functionis accomplished in firmware. While completely functional, the 7-bit performance isaffected because it works through software emulation. Therefore, this mode has a
noticeable latency and character per second processing limit. Roving Networks does
not recommend using this mode if the desired serial baud rate is greater than 9,600.

3.7.5

Common Issues

The following sections provide some solutions to common issues.
3.7.5.1

MY BLUETOOTH CLIENT CAN SEE THE FIREFLY MODULE AND ITSSERIAL SERVICE, BUT I CAN’T CONNECT

This issue is most likely caused by a security setting on your client. The FireFly module
supports authentication by default if the client requires it (with the default pin code of1234), but for ease of use, you may want to turn security off on your client. Some clients
have these settings turned off by default, others have them turned on. To check anddisable security, perform the following steps from a Windows PC:
1. Click My Bluetooth Places.
2. Click the Client Applications tab under Bluetooth Device Configuration (orAdvanced Configuration).
3. Click the Bluetooth serial port application name.
4. Click the Properties button.
5. If Secure connection, Authentication, or Encryption is turned on, turn it off.
6. Click OK.
3.7.5.2

HOW DO I CHANGE THE CLIENT’S COM PORT?

The Widcomm stack, the most commonly used stack, allows you to connect to the FireFly module using a virtual COM port mapper. The software installs with a default COM
port, usually COM3, COM4, or COM5. To change this setting, perform the following
steps on a Windows PC:
1. Click My Bluetooth Places.
2. Click the Client Applications tab under Bluetooth Device Configuration (orAdvanced Configuration).
3. Click the Bluetooth serial port application name.
4. Click the Properties button.
5. Change the COM port setting.
6. Click OK.

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3.7.5.3

HOW DO I CONNECT TO MORE THAN ONE FIREFLY MODULE FROMTHE SAME CLIENT AT THE SAME TIME?

Bluetooth allows 7 devices to connect at a time in a piconet. The Widcomm stack allows
you to create multiple instances of the serial port profile and connect to multiple FireFly
modules at the same time. To connect to multiple modules, perform the following steps
on a Windows PC:
1. Click My Bluetooth Places.
2. Click the Client Applications tab under Bluetooth Device Configuration (orAdvanced Configuration).
3. Click the Bluetooth serial port application name.
4. Click the Add COM Port button.
5. Add another Bluetooth serial port and assign it to another virtual COM port (suchas COM9).
6. Click OK.

3.7.6

Discovery & Connection Example Sequence

The following example goes through a master discovery/connection sequence frompower up and no connection.
1. Perform an inquiry to obtain the Bluetooth address (unless it is already known).
Send: $$$// Places radio in command mode
Reply: CMD<cr>
Send: I,30<cr>// Look for Bluetooth devices
Reply: 00A096112233,1F00<cr>Inquiry Done<cr>
2. Store the remote address that you just found.
Send: SR,00A096112233<cr>// or type SR,I if this was the only device// found

Reply: AOK<cr>
3. Connect.
Send: C<cr>
Reply: AOK<cr>// Places the radio in connect mode

The device attempts to connect to the remote slave. The terminal displays TRYING
while the device attempts to connect.
Reply:<string>CONNECT<cr>// Where <string> is an alphanumeric// string defined in the stored parameters

4. Send/receive data.

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3.7.7

Auto-Pairing/Auto-Connection

You can use the GPIO pins/dipswitches for auto-pairing and auto-connection. Table 3-8
shows the function for various settings of the GPIO pins/dipswitches.
TABLE 3-8:

GPIO PIN/DIPSWITCH SETTINGS FOR AUTO-PAIRING/CONNECTION

GPIO3/Dipswitch 2 GPIO6/Dipswitch 3
Low

Function

Low

Default slave, no special function.

High

Low

Slave, changes COD to 0x0055aa for auto pairing.

Low

High

Auto master, the module uses the stored address and does not try auto
pairing.

High

High

Auto master, auto pairing, the module looks for the first device with
0x55aa, stores it, and connects to it.

To enable cable replacement, set GPIO3 high on the slave device and GPIO3 andGPIO6 high on the master. Once paired, GPIO3 is low on both devices (so re-pairingwith another Roving Networks device does not occur).

3.8

SERIAL ADAPTER CONFIGURATIONThe Bluetooth serial adapters have male or female DB9 connectors. Refer toFigure 3-1 and Table 3-9 for the pin-out.
FIGURE 3-1:

DB9 CONNECTOR PINS
1

5

6TABLE 3-9:Pin

DB9 CONNECTOR PIN-OUT

RN220XP& RN270M
Male DB9

RN240F & RN270F
Female DB9

RN422M & RN274M
Male DB9

1

NC

NC

NC

2

RXD

TXD

NC

3

TXD

RXD

RXD-

4

NC

NC

TXD+

5

GND

GND

GND

6

NC

NC

+5 VDC (Input)

7

RTS

CTS

RXD+

8

CTS

RTS

TXD-

9

4 – 12 VDC

4 – 12 VDC

NC

Note:

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9

The RS-232 interface uses the SIPEX SP3232ECA chip with capacitor
switch to generate the + and – signals; therefore, it is not driving the full
RS-232 voltages. Devices stealing power from the RS-232 pins may nothave enough voltage.

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3.9

NULL MODEM & FLOW CONTROL JUMPERS
You can configure the adapter’s serial interface to enable flow control and null modem
signaling. You access the jumper block by removing the cover from the Bluetooth serial
adapter. Figure 3-2 and Figure 3-3 show the jumper settings.
FIGURE 3-2:

RN422, RN240, RN270 & RN274 JUMPERS

Male DB9 (Default Configuration)
DTE 3 Wire - Flow Control Disabled
Jumper 1 < > 2, 3 < > 4, 9 < > 10
1
3
5
7
9

2
4
6
8
10

Male DB9
DTE - Flow Control Enabled
Jumper 1 < > 2, 3 < > 4, 5 < > 6, 7 < > 8
1
3
5
7
9

2
4
6
8
10

Male DB9
DCE - Flow Control Enabled, Null Modem
Jumper 1 < > 3, 2 < > 4, 5 < > 6, 7 < > 8
1
3
5
7
9

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2
4
6
8
10

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Female DB9 (Default Configuration)
DTE 3 Wire - Flow Control Disabled
Jumper 1 < > 3, 2 < > 4, 9 < > 10
1
3
5
7
9

2
4
6
8
10

Female DB9
DTE - Flow Control Disabled
Jumper 1 < > 3, 2 < > 4, 5 < > 6, 7 < > 8
1
3
5
7
9

2
4
6
8
10

Female DB9
DTE - Flow Control Enabled
Jumper 1 < > 2, 3 < > 4, 5 < > 7, 6 < > 8
1
3
5
7
9

2
4
6
8
10

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FIGURE 3-3:

RN220XP JUMPERS

Male DB9 (Default Configuration)
DTE 3 Wire
Jumper 1 < > 2, 7 < > 8, 9 < > 10
1
3
5
7
9

Male DB9
DCE - Flow Control Disabled
Jumper 1 < > 2, 7 < > 9, 8 < > 10

2
4
6
8
10

1
3
5
7
9

2
4
6
8
10

Male DB9
DCE - Flow Control Enabled
Jumper 3 < > 4, 5 < > 6, 7 < > 8, 9 < > 10
1
3
5
7
9

3.10

2
4
6
8
10

DIPSWITCH SETTINGS
The adapters have small configuration dipswitches on the top. You need a paper clip
or small screwdriver to flip them. Holding the adapter with the DB9 connector facing to
the right, refer to Figure 3-4 for the dipswitch numbering and on/off positions.
FIGURE 3-4:

DIPSWITCHES

RN240, RN422 & RN220XP
On

Off

4
3
2
1

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RN270 & RN274
On

Off

4
3
2
1

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Table 3-10 describes the functions controlled by the dipswitches.
TABLE 3-10:
Dipswitch

SWITCH FUNCTIONSFunction

Description

1

Restore factory defaults Turn on the switch, power up the adapter, and toggle the switch
ON-OFF-ON-OFF-ON to return the adapter to its factory settings. The green
LED blinks quickly for a moment and then continues to blink about once persecond.

2

Automatic discovery

In slave mode, this dipswitch sets a special class of device that is used by themaster to auto connect. If dipswitch 3 also turned on, the adapter performs asearch, stores, and connects to a remote Roving Networks Bluetooth device
that has dipswitch 2 turned on.

3

Automatic masterWith this dipswitch turned on, the adapter acts as Bluetooth master andauto-connects to a stored remote address. You must first set the Bluetooth
address of the slave device using the SR command or using instant cablereplacement settings.

4

Default baud rate

With this dipswitch turned off, the default 115 K baud rate is overridden by software baud rate configuration commands. If this dipswitch is turned on, thebaud rate is 9600 and the adapter ignores the software configuration.

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Chapter 4. Applications
The following sections describe how to use Roving Networks Bluetooth devices for
instant cable replacement.

4.1

INSTANT CABLE REPLACEMENT
You can configure a pair of Roving Networks serial adapters (with or without the FirePlug USB dongle, RN-USB-X) to provide an instant serial cable replacement. The two
adpaters are paired using either:• Hardware pairing via dipswitches• Configured using software commands

4.1.1

Hardware Pairing Using Dipswitches

To pair using hardware, perform the following steps:
1. Turn off the adapters and set the dipswitches as shown in Figure 4-1.
FIGURE 4-1:

CABLE REPLACEMENT DIPSWITCH SETTINGS FOR
Master Mode
Auto Discovery &Auto Master Turned On
On

Slave Mode
Auto Discovery Turned On

Off

4
3
2
1

On

Off

4
3
2
1

PAIRING
2. Power up both devices. The master discovers the slave device, stores its Bluetooth address, and connects. The devices are now paired and each device’s
green LED should be on solid.
3. The devices are now paired. Set dipswitch 2 on both devices to off so that they
do not try to re-pair each time power is cycled. See Figure 4-2.
FIGURE 4-2:

SETTING DIPSWITCH 2 FOR DEPLOYMENTMaster ModeOn

Slave Mode

Off

4
3
2
1

On

Off

4
3
2
1

Once paired, when the devices are in range of each other, they connect and the masterwill not attempt to connect to any other Bluetooth device. To break the pairing, restore
the factory defaults using dipswitch 1.

4.1.2

Software Pairing Using Commands

To configure the master and slave devices for instant cable replacement, connect yourterminal emulator on the host to the devices via the COM port using the settings
115,200 baud, no parity, 8 bits, 1 stop bit, and no flow control.
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On the slave device, issue the following commands:
1. Put the device in command mode by sending the $$$ command. The device
returns CMD to indicate it is in command mode.
2. Send SM,0<cr> to put the device into slave mode.
3. Verify that the device is in slave mode by issuing the D action command. Look
for the MODE =Slav message.
4. Reboot the device using the R,1<cr> command. The changes do not take effectuntil the device is rebooted.
On the master device, issue the following commands:
1. Put the device in command mode by sending the $$$ command. The device
returns CMD to indicate it is in command mode.
2. Send SM,1<cr> to put the device into slave mode.
3. Verify that the device is in slave mode by issuing the D action command. Look
for the MODE =Mstr message.
4. Ensure that the slave device is turned on, and send the I<cr> inquire command.
5. Locate the slave’s (remote side) Bluetooth address (BTA) in the results of theinquiry command. The BTA is a 6-byte (12 hex-characters) value.
6. Store the remote BTA using the SR,<address><cr> command. For example, if
the remote BTA is 000666037083, enter the command SR, 000666037083<cr>to store the remote address.
7. Reboot the device using the R,1<cr> command. The changes do not take effectuntil the device is rebooted. The master device restarts and connects with theremote slave device. A solid green LED indicates that the devices are connected.
For more information on instant cable replacement, refer to the Bluetooth Cable
Replacement Application Note on the Roving Networks website at http://www.rovingnetworks.com/Support_Overview.

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Chapter 5. HID Profile
5.1

OVERVIEW
Roving Networks Bluetooth modules support a variety of Bluetooth profiles, including
human interface device (HID), serial port profile (SPP), DUN, HCI, and iAP for use with
iPad, iPod and iPhone devices. The Bluetooth HID profile enables customers todevelop wireless products such as computer keyboards and keypads, trackballs, mice,and other pointing devices, and game controllers (gamepads, joysticks, steering
wheels, etc.). Additionally, Roving Networks has extended the basic HID capability toallow programmability and control of devices such as the iPad.
The HID profile defines the protocol between:• Device (HID)—Services human data input and output to and from the host.
• Host—Uses or requests the services of a human interface device.
The Bluetooth HID profile allows users to control the HID descriptor, which defines thedevice’s feature set, and the HID report, which host uses to interpret the data as ASCII
values, movement, etc. The HID report format follows the standard universal serial bus(USB) HID protocol as to leverage existing host drivers.
In a typical usage scenario such as a keyboard, a device using the Roving Networks
Bluetooth HID profile replaces the USB cable. In this case, the ASCII value of a key
press is converted to a scan code in a raw HID report that the Bluetooth module sends
over the Bluetooth link to the host. The host driver software decodes the raw HID reportand passes the key values to the application running on the PC. Figure 5-1 showssome typical HID environments.

FIGURE 5-1:

TYPICAL HID ENVIRONMENTS

The type of HID device, such as a keyboard, mouse, or joystick, is defined by the HID
descriptor in the raw HID report.

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5.2

HID FIRMWARE OVERVIEW
To use Roving Networks’ Bluetooth HID profile, you must use a special build of firmware, version 6.03 or later.
Note:

5.2.1

Roving Networks modules shipped with firmware version 6.11 and higher
support the HID profile. You do not need special firmware if your module isrunning firmware 6.11 or higher.

Operational Modes

Roving Networks Bluetooth modules operate in two modes: data mode (default) andcommand mode. While in data mode, the module is essentially a data pipe. When themodule receives data, it strips the Bluetooth headers and trailers and passes the user
data to the UART. When data is written to the UART, the module constructs the Bluetooth packet and sends it out over the Bluetooth connection. Thus, the entire processof sending/receiving data to the host is transparent to the end microprocessor.
You configure the module by putting it into command mode and sending ASCII commands over a serial port or the Bluetooth link. Once you change the configuration
parameters, they persist until changed or you perform a factory reset. You enter command mode by opening a terminal emulator and sending the string $$$ to the module.
You can connect to the module remotely over Bluetooth or via a computer. When you
send $$$ the module returns CMD, indicating that it is in command mode.
Once the module is in command mode, you can send configuration commands to it via
the terminal. When you enter a valid command, the module returns AOK. It returns ERR
for an invalid command and ? for unrecognized commands. Type H<cr> to see a list ofcommands, and D<cr> to view a summary of the module’s current settings. To return todata mode, type ---<cr> or reset the device and re-connect.

5.2.2

Profile Configuration

The HID firmware supports Bluetooth HID and SPP. You switch between these profiles
using ASCII commands. In firmware version 6.10 and higher, the SPP profile is enabled
by default. To switch between HID and SPP, use the following commands:
S~,0// Enables SPP protocol

R,1// Reboot to use SPP

To switch back to HID, use the following command:
S~,6// Enables HID profile

R,1// Reboot to use HID profile

5.2.3

Device Discovery & Pairing

During pairing, the module determines the HID device type. As part of the Bluetooth
protocol, the HID device sends the type. By default, the Roving Networks’ modules running the HID profile are discoverable as a keyboard. You can change the device typeby setting the descriptor type using the HID flags register.

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After first pairing the host to a device with the Bluetooth HID module, the host initiates
a connection. However, if the initial connection is broken, as the case when the poweris cycled, the device must re-connect to the host. (The host will not initiate a connection.)
Using DTR mode 4 (default) or pairing mode 6 allows the module to auto-connect backto the last paired host. Alternatively, you can reconnect by sending the C commandfrom command mode. See the following examples:
SM,4// Use GPIO6 to make and break// connections

SM,6// Automatically make connections// without using GPIO6

5.2.4

HID Flag Register

The HID flag register is a bit-mapped register that is configured while in commandmode. To set the register, use the SH,<value> command, where <value> is a 4-character hex word. The GH command returns the current value of the register. The default
factory setting is 0000, which corresponds to a keyboard. Table 5-1 shows the HID flagregister bits; currently only the lower 9 bits are defined.
TABLE 5-1:

HID FLAG REGISTER BITS

9
Force HID mode if
GPIO11 is high on
power-up.

8

7..4

Toggle virtual key- Descriptor type:board on iOS when
first connected.
0000 = Keyboard
0001 = Game Pad
0010 = Mouse
0011 = COMBO
0100 = JOYSTICK
1XXX = Reserved

5.2.4.1

3

2..0

Send output reports
over UART.

Indicates number of paired
devices to which the module
can reconnect.

BIT 9

Bit 9 is an enable bit that overrides the profile selection mode. When this bit is set, thefirmware checks the level of GPIO11 on power up; if it is high, the module switches to
HID mode. With this bit, you can set the module’s default profile to SPP mode, allowing
SPP and remote configuration (for example from Bluetooth clients with SPP). Then,
you can use GPIO11 to override SPP mode and enable HID mode.
Note:

5.2.4.2

GPIO11 HID profile switching is disabled when the module is configured for
the MDM SPP profile (S~,3). GPIO11 is reserved for RTS in MDM SPP
mode.
BIT 8

Bit 8 enables the toggling of the virtual keyboard on iOS devices.
5.2.4.3

BITS 7-4

Bits 7 through 4 control the following settings:• The COD that is advertised by the module.
• The HID report descriptor and the available reports.

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5.2.4.4

BIT 3

Bit 3 enables output reports, which are sent by the host to the device over Bluetooth to
the UART. These reports are a feedback mechanism to the embedded microcontroller.
The output record is formatted as:<start> <number of bytes>
0xFE

1–8

<report>data

For example, the HID keyboard output reports the keyboard LED status as:
0xFE

0x2

5.2.4.5

0x1 <LED status byte>

BITS 2-0

Bits 2 through 0 define the number of paired hosts to which the module attempts toreconnect after power up. After each successful pairing, the link key is stored in the Bluetooth module. Up to eight paired link keys are stored in FIFO fashion. Upon powerup, the module tries to connect to the most recently paired device. If it is not found, themodule attempts to connect to the next N hosts depending upon the settings of bits 2-0
in the HID register.
For example:• To set the device as a mouse, use SH,0220.
• To set the device as a combo mouse, use SH,0230.

5.3

HID REPORTS
The module interprets input on the UART and generates an HID report that is sent overthe Bluetooth link to the host. Input to the module is interpreted as shown in Table 5-2
TABLE 5-2:
DATA INTERPRETATION
Binary Input

Function

0

Disconnect if connected from the host.

0x1 - 0xF

Converted to special keys like home, page up, backspace, etc.

0x10 - 0x7E

Translation mode: printable ASCII characters.

0x7F

Toggle virtual keyboard on iPhone.

0x80 - 0xDF

Interprets input as actual scan code.

0xE0 - 0xE7

Sends modifier keys Left Shift, Left Alt, Right Shift, etc.

0xE8 - 0xEF

Interprets input as actual scan code.

0xF0 - 0xFC

Reserved for custom reports.

0xFD

Raw mode: input is RAW report.

0xFE

Interpretive mode: input is shorthand report.

0xFF

Sends output report to UART.

See “Scan Code Tables: UART (ASCII) to HID Report” on page 67 for a complete tableof UART input to HID report.

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5.3.1

Translation Mode

Translation mode is the simplest way to send HID reports for printable ASCII characters. When the Bluetooth module’s UART receives a printable ASCII value, it is converted into a keyboard raw HID report. Two reports are sent for each character; the firstreport indicates that the key is pressed and the second indicates that it is released. For
example:a is translated into:
0xFD

0x9

0x1

0x0

0x04

0x0

0x0

0x0

0x0

0x0

0x0

0x0

0x0

Key Press

0xFD

0x9

0x1

0x0

0x00

0x0

0x0

0x0

0x0

0x0

0x0

0x0

0x0

Key Release

A is translated into:
0xFD

0x9

0x1

0x2

0x0

0x04

0x0

0x0

0x0

0x0

0x0

0x0

0x0

0x0

Key Press

0xFD

0x9

0x1

0x0

0x00

0x00

0x0

0x0

0x0

0x0

0x0

0x0

0x0

0x0

Key Release

Notice that the scan code for A is the same as the previous raw report except the modifier byte indicates the left Shift key is pressed. If multiple scan codes are sent, the modifier applies to all of them.

5.3.2

Keyboard Shorthand Mode

The Roving Networks HID profile supports shorthand for implementing keyboards. The
advantage of this mode is that multiple keyboard keys can be sent with minimal characters over the UART, which optimizes bandwidth because the module does not haveto send a keyboard report. Shorthand reports start with 0xFE and have variable length.
The shorthand format is:
0xFE

LengthModifier

Scan
Code 1

Scan
Code 2

Scan
Code 3

Scan
Code 4

Scan
Code 5

Scan
Code 6

where Length = 0, 2, 3, 4, 5, 6, or 7, depending on how many keys are sent.
For example, shorthand for the a, b, and c keys is:
0xFE

0x3

0x0

0x4

0x05

0x06

The Bluetooth module converts this shorthand into the following raw HID reports thatare sent over the Bluetooth link:
0x9

0x1

0x0

0x04

0x5

0x6

0x0

0x0

0x0

0x0

0x0

0x0

Shorthand to release all three keys is:
0xFE

5.3.3

0x0

Raw Report Mode

The start byte 0xFD indicates a raw HID report. In the Bluetooth module, the start byte
is stripped and the following bytes are sent without interpretation. The Raw HID reportconsists of a start byte, length, descriptor type (which defines the type of HID device),and data specified in scan codes or encoded values. The format of the data depends
on the descriptor type. HID reports are sent one report at a time.

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The raw report format is:
Start(1Byte)Length(1 Byte)Descriptor(1 Byte)

Data
Length – One Byte for the Descriptor

The keyboard report format is:
0xFD

9

1

Modifier

0x00

Scan
Code 1

Scan
Code 2

Scan
Code 3

Scan
Code 4

Scan
Code 5

Scan
Code 6The modifier byte is a bit mask interpreted as shown below. For example, you can use
0x2 or 0x20 to turn a lower case a into an upper case A.
Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Right
GUI

Right
Alt

Right
Shift

Right
Ctrl

Left
GUI

Left
Alt

Left
Shift

Left
Ctrl

The mouse raw report format is:
0xFD

5

2

Buttons

X-stopY-stopWheel

The consumer report format in keyboard or combo mode is:
0xFD

3

3

Data Byte

Data Byte

The joystick and gamepad format is:
0xFD

6

Buttons
0-7

Buttons
8 - 15

X1
Note 1

Note 1:

The range of X and Y is -127 to 127.

Y1
Note 1

X2
Note 1

Y2
Note 1

In combo mode, it is possible to send both for a keyboard and mouse HID reports. In
this case, if you wanted to enter an A and move the mouse you can use either of thefollowing methods:
A:
0XFD

0x5

0x2

0x0

0x1

0x20

0x20

0x20

0x0

0x0

or
0xFD

0x9

0x1

0x2

0x0

0x04

0x0

0x0

0XFD

0x5

0x2

0x0

0x1

0x20

0x20

0x20

5.3.4

0x0

0x0

0x0

0x0

Special Reports & Modes

This section describes special modes and reports, including output reports, virtual keyboards, a key-map register, etc.
5.3.4.1

OUTPUT REPORTS

Because the host controls the modifier keys’ state, the HID device must be able torequest the current status. The output report code 0xFF is reserved to return the current
status of the Caps Lock, Num Lock, and Scroll Lock keys over the UART. Because a
HID device can only toggle these keys, it tells the device the state of the keys. Thisfunctionality is particularly useful when multiple HID devices are in the system and theBluetooth device needs to update the state of these keys. The format is sent as:
0xFF

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Status
Byte

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Table 5-3 shows the status byte definitions.
TABLE 5-3:
STATUS BYTE DEFINITIONS

5.3.4.2

Key

Status Bit

Num Lock1

Caps Lock

2

Scroll Lock

4

APPLE VIRTUAL KEYBOARD

When the module is connected to an iOS device, the virtual keyboard is hidden. However, in some applications it is useful or required to display the keyboard for data entry
on the touch screen of the iOS device. Toggling GPIO9 displays or hides the virtual keyboard. GPIO9 must go from low to high for at least 200 ms for the toggle to occur.
Note:

5.3.4.3

The virtual keyboard toggle must be enabled in the HID flag register for thisfeature to work.
KEY MAP REGISTER

This register allows you to replace any ASCII code with another ASCII code. It is usefulin cases where you want to toggle special keys that the device cannot generate. For
example, the touch keyboard on an iOS device is 0x7F, but the device cannot generate
0x7F.
If the register is non-zero, the upper byte is the key to replace, and the lower is thereplacement. The command to set the register is S=,< value>, where <value> is a4-character hex word. To obtain the current value of the register, use the G= command.
(The value also shows up in the advanced settings using the E command.) The default
factory setting is 0000 (not enabled).
For example, to use the tilda (~), which is 0xfe, to toggle the keyboard, enter the command S=,7e7f.
5.3.4.4

DISCONNECT KEY

A special hex key value 0x00 (zero) causes a Bluetooth disconnect, which allows you
to control the connection by sending a single key. To disconnect, send 0x0.
Combining the disconnect feature with the key map register, any key can be used as a
disconnect key. For example to set the capital Z key (hex 5A) as the disconnect key,use the following command:// Map Z key as the disconnect key

S=,5A00

5.3.4.5

CONSUMER REPORTYou can use a HID raw report to send additional keys as a consumer report. The format
is:
0xFD

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3

3

Low Byte

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Table 5-4 shows the data byte format.
TABLE 5-4:
DATA BYTE FORMAT
Consumer Key Function

Report Bit

AC Home0x1

AL Email Reader

0x2

AC Search

0x4

AL Keyboard Layout (Virtual Apple Keyboard Toggle)

0x8

Volume Up

0x10

Volume Down

0x20

Mute

0x40

Play/Pause

0x80

Scan Next Track

0x100

Scan Previous Track

0x200

Stop

0x400

Eject

0x800

Fast Forward

0x1000Rewind0x2000

Stop/Eject

0x4000

AL Internet Browser

0x8000For example, to raise the volume, send:
0xFD

0x03

0x03

0x10

0x00

To release the key, send:
0xFD

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0x03

0x03

0x00

0x00

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5.3.4.6

SCAN CODE TABLES: UART (ASCII) TO HID REPORT

Table 5-5 shows the UART-to HID input conversion.
TABLE 5-5:
UART-TO-HID SCAN CODE
UART Input

HID Code

0

NA

1

0x49

Insert

2

0x4A

Home

3

0x4B

Page up4

0x4C

delete

5

0x4D

end

6

0x4E

Page down

7

0x4F

Right arrow

8

0x2A

Backspace

9

0x2B

TAB

10

0x28

Enter

11

0x50

Left arrow

12

0x51

Down arrow

13

0x28

Enter

14

0x52

Up arrow

15-26

0x3A-45

F1 - F1227

0x29

Escape28

0x39Caps lock

29

0x47

Scroll lock

30

0x48

Break-pause

31

0x53

Num lock32-126www.rovingnetworks.com

HID Function
Disconnect if Connected

Printable ASCII characters

127

0x65

Toggle iPhone virtual keyboard

0x80-0xDF

0x80-0xDF

Sends actual scan code

0xE0

0xE0

Left Control

0xE1

0xE1

Left Shift

0xE2

0xE2

Left Alt

0xE3

0xE3

Left GUI

0xE4

0xE4

Right Control

0xE5

0xE5

Right Shift

0xE6

0xE6

Right Alt

0xE7

0xE7

Right GUI

0xE8-0xEF

0xE8-0xEF

Sends actual scan code

0xF0-0xFC

Reserved for future use

Custom reports

0xFD

Raw report

0xFE

Shorthand report

0xFF

Sends output report to UART

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Table 5-6 shows the ASCII to HID report scan codes.
TABLE 5-6:

ASCII TO HID REPORT (TO HOST) SCAN CODES

ASCII

Code

ASCII

Code

System Power

81mM

System Sleep

82

nN

11

7&

System Wake

83

oO

12

8*

10

ASCII
6^

Code
23

ASCII

Code

.>

37

24

/?

38

25

Caps Lock

39

No Event

00

pP

13

9(

26

F1

3A

Overrun Error

01

qQ

14

0)

27

F2

3B

POST Fail

02

rR

15

Return28

F33C

ErrorUndefined

03

sS

16

Escape

29

F4

3D

aA

04

tT

17

Backspace

2A

F5

3E

bB

05

uU

18

Tab

2B

F6

3F

cC

06

vV

19

Space

2C

F7

40

dD

07

wW

1A

-_

2D

F8

41

eE

08

xX

1B

=+

2E

F9

42

fF

09

yY

1C

[{

2F

F10

43

gG

0A

zZ

1D

]}

30

F11

44

hH

0B

1!

1E

\|

31

F12

45

iI

0C

2@

1F

Europe 132

Print Screen

46

jJ

0D

3#

20

;:

33

Scroll Lock

47

kK

0E

4$

21

‘“

34

Break (Ctrl-Pause)

48

lL

0F

5%

22

,<

36

Pause

48

5.4

HID REFERENCES[1] Bluetooth SIG, Human Interface Profile Overview
URL: https://www.bluetooth.org/Building/HowTechnologyWorks/ProfilesAndProtocols/HID.htm[2] USB.org, HID Usage Tables
URL: http://www.usb.org/developers/devclass_docs/Hut1_12v2.pdf[3] USB.org, HID Technology
URL: http://www.usb.org/developers/hidpage/www.rovingnetworks.com

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Appendix A. Factory Defaults
Table A-1 shows the factory default settings.
Note:

TABLE A-1:

Restoring the device to the factory default values resets all values to thedefaults shown in Table A-1.

FACTORY DEFAULT SETTINGS
Setting

Default Value

Bluetooth Service Profile

Serial Port Profile (SPP)

Device Mode

4 (DTR)

Baud Rate

115,200 bps

ParityNone

Data Bits

8 BitsStop Bits

1 Bit

Power Mode

Auto Low-Power Discoverable Mode

Device Name (Local Name)

FireFly-xxxx (last 2 bytes of the Bluetooth Address)

Service Class

SPP

Service Type

0000 (Undefined Service Type)Class of Device (COD)

0x1F00 (Unknown Device Type)

Authentication

Keybboard I/O simple secure pairing (SPP)

Discovery Enabled

0x0100 Window, Fixed Interval of 0x1000

Connection Enabled

0x0100 window, Fixed Interval of 0x1000

Bonding

Disabled

Configuration Timer

60 seconds

Sniff Mode

Disabled

Default Pin

1234

Hide Pin Code0, Disabled

Local Echo of RX Characters in Command Mode

OFF

Power

0010 (Maximum Power)

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Appendix B. Command Quick Reference Guide
This section provides a quick reference of the firmware commands as well as the factory defaults. Table B-1 provides an overview of the set commands.
TABLE B-1:

SET COMMANDS

Command

Description

Factory Settings

S7,<1,0>7-Bit Data Mode Enable/Disable.

0, DisabledSA,<0,1,2,4>Authentication Enable/Disable.

0, Disabled

SB,<value>

Send Break.

Not Applicable

SC,<value>

Service Class.

0x0000, Unknown

SD,<value>

Device Class.

0x1F00, UndefinedSE,<string>

Sets the UUID for SPP Data Connections.

0x1101SF,1Factory Defaults.

N/A

SH,<value>

Sets the HID flag register (HID firmware only).

0200

SI,<hex value>

Inquiry Scan Window.

0x0100SJ,<hex value>

Page Scan Window.

0x0100SL,<E,O,N>

Parity.

N, NoneSM,<0,1,2,3,4,5>Mode (0 = Slave, 1 = Master, 2 = Trigger, 3 = Auto, 4 = DTR, 5 =Any).

4, DTR

SN,<string>

Name.

FireFly-xxxx

SO,<string>

Connect/Disconnect Status String.

NULL, No Status String

SP,<string>

Pin Code.

1234

SQ,<mask>

Special Configuration Settings.

0SR,<hex value>

Remote Address (Use SR,Z to Remove).

None Set

SS,<string>Service Name.

SPP

ST,<value>

Configuration Timer.

60 Seconds

SU,<value>

Baud Rate.

115 K

SW,<value>

Sniff Rate.

0x0000, Disabled

SX,<1,0>Bonding.

0, Disabled

SY,<hex value>

Power Setting.

0010

SZ,<value>

Raw Baud Rate.

N/A

S|,<value>

Low-Power Connection Mode.

0000

S~,<0, 1, 2, 3, 4, 5, 6> Profile Setting (0 = SPP, 1 = DUN-DCE, 2 = DUN-DTE, 3 = MDM
SPP, 4 = DUN-DCE & SPP, 5 = APL, and 6 = HID).

0, SPP

S-,<string>

Sets the Serialized Friendly Name of the Device.

N/A

S?,<0,1>

Enable/Disable Role Switch.

0, Disabled

S$,<string>

Configuration Detection Character.

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Table B-2 describes the get (or display) commands.
TABLE B-2:
GET (DISPLAY) COMMANDS
Command

Description

D

Basic Settings.

E

Extended Settings.

G<string>

Displays Setting for a Set Command Indicated by <string>.

GB

Bluetooth Address.

GK

Connection Status.

GF

Bluetooth Address of Currently or Most Recently Connected Active Remote
Device.

GR

Remote Address.

G&

I/O Ports.

H

Help.

M

Remote Modem Signal Status.

O

Other Settings.

V

Firmware Version.

Table B-3 describes the action commands.
TABLE B-3:

ACTION COMMANDS (PART 1 OF 2)

Command

Description$$$

Enter Command Mode.

---

Exit Command Mode.

+

Toggle the Local Echo of RX Characters in Command Mode.

&

Return the Dipswitch Values.

C

Connect Immediately to the Stored Remote Address.

C,<address>

Connect to Address.

CF<address>

Connect to Address in Fast Mode.

CFI

Connect and Immediately Go into Fast Data Mode Using Last Address Found.

CFR

Connect to Stored Remote Address in Fast Mode.

CT<address>,<value>

Connect, Address Required, Optional Disconnect Timer in ¼ Seconds.

F,1

Enter Fast Data Mode, End Configuration Immediately.

I,<value>,<COD>

Device Scan Inquiry, Time in Seconds, Optional COD Filter (0 = All).

IN<value>,<COD>

Device Scan Inquiry, Returns NAMEs.

IQ

Scans for Devices and Returns their RSSI.

IS<value>

Device Scan Inquiry, Fixed COD (0x001F00) to Find Roving Networks Devices.

IR<value>

Device Scan Inquiry, Fixed COD (0x0055AA) to Find Instant Cable Pairs.

J

Hides the Device’s Pin Code.

K,

Kill (Disconnect) from Current Connection.

L

Toggle Link Quality Readings.

P,<char>

Pass through Any Character up to a Carriage Return or Line Feed.

Q

Quiet, Turn off Discovery and Connectability.

R,1

Reboot.

T,<0,1>

Pass Received Data (from UART or Bluetooth) while in Command Mode.

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TABLE B-3:

ACTION COMMANDS (PART 2 OF 2)

Command

Description

U,<value>,<E,O,N>

Temporary UART Change.

W

Re-Enable Discovery and Connectability.

Z

Enter Low-Power Sleep Mode.

Table B-4describes the GPIO commands.
TABLE B-4:

GPIO COMMANDS

Command

DESCRIPTION

S@,<hex value>

Set the GPIO pin’s direction (input or output). This setting is lost when power is cycled.

S&,<hex value>

Set the GPIO pin’s value. This setting is lost when power is cycled.

S%,<hex value>Store the GPIO pin’s direction for use on power up.

S^,<hex value>Store the GPIO pin’s powerup value.

S*,<hex value>

Set values for GPIO8, GPIO9, GPIO10, and GPIO11.

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Appendix C. Firmware Revision History
The following sections provide the firmware revision history.

C.1

VERSION 6.15 (3/26/2013)This firmware replaces version 4.77. Designers are encouraged to create all new
designs based on firmware version 6.15 and higher.
• The following commands that were changed or deprecated in version 6.11 havebeen restored in 6.15 to maintain backwards compatibility (command level) withfirmware version 4.77.
- L—This command displays the minimun and maximium RSSI values.
- Q—Places the module in a non-discoverable mode (same as Q,1 in firmware
6.12)- W—wakes up module (same as Q,0 in firmware 6.12)• Changes to commands available in firmware 6.12:- Q,? displays the current quiet mode (in firmware 6.12, you use the Q command to display the mode).
- SE,(0,1) are null commands in firmware 6.15 to maintain compatibility withfirmware 4.77 command syntax.
• Inquiry and Page scan defaults to 0x0100 for compatibility with firmware 4.77. In
firmware 6.11/6.12, the page interval was set to 0x0060.

C.2

VERSION 6.12 (LIMITED RELEASE)• Incorporates the HID profile into the standard firmware.
• Added the J command to hide the device’s pin code. This command replaces the
SV,1 command (hide or show the pin code).
• Updated the IQ command to include RSSI inquiry scanning.

C.3

VERSION 6.11
No new features. Improved code to make it more maintainable.
Inquiry and page interval set to 0x0060.

C.4

VERSION 6.10
• Added additional functionality to the Q command to enable/disable device discovery and ability to connect.
• Added authentication modes: open mode, keyboard mode, SSP mode, and pin
code mode.
• Encryption is enabled by default and cannot be disabled.
• Added the ability to store a custom UUID in the device.

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C.4.1

HID Firmware Known Issues• The HID firmware has difficulty maintaining a connection with the first generation
iPAD running iOS version 4.4; you must upgrade to iOS version 5 to use the iPadwith the HID firmware.
• The HID profile does not appear to work with BlueSoleil.

C.5

VERSION 4.77 (8/10/2009)• Fixed issue where disconnect followed by a fast reconnect (< 100 ms) would cause themodule to go (deaf) making it undiscoverable or connectable, requiring a reset.

• Fixed issue where <cr><lf> characters often were sent out the UART when entering fast
data mode using the F,1 command remotely.

• Added the S| command to reduce power while waiting for a connection.
• Added CF, CFI, and CFR commands for fast data mode connections.
• Added L command to display link quality.
• Added + command to toggle local echo of characters in command mode.

C.6

VERSION 4.74 (3/7/2009)• Added support for SPP and DUN simultaneous profile appearance.

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Appendix D. Document Information
CONVENTIONS USED IN THIS GUIDEThis manual uses the following documentation conventions:
DOCUMENTATION CONVENTIONS
Description

Represents

ExamplesReferenced books
Emphasized text
A window
A dialog
A menu selection
A field name in a window or
dialogA menu path

MPLAB® IDE User’s Guide...is the only compiler...
the Output window
the Settings dialog
select Enable Programmer“Save project before build”

A dialog button
A tab
A number in verilog format,
where N is the total number ofdigits, R is the radix and n is adigit.
A key on the keyboard

Click OK
Click the Power tab
4‘b0010, 2‘hF1

Italic Courier New

Sample source code
Filenames
File paths
Keywords
Command-line options
Bit values
Constants
A variable argument

Square brackets [ ]Optional arguments

Curly braces and pipecharacter: { | }Ellipses...

Choice of mutually exclusive
arguments; an OR selection
Replaces repeated text

#define START
autoexec.bat
c:\mcc18\h_asm, _endasm, static-Opa+, -Opa0, 1
0xFF, ‘A’
file.o, where file can be
any valid filename
mcc18 [options] file
[options]
errorlevel {0|1}Arial font:
Italic characters
Initial caps

QuotesUnderlined, italic text withright angle bracket
Bold characters
N‘Rnnnn

Text in angle brackets < >Courier New font:
Plain Courier New

Represents code supplied byuser

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File>Save

Press <Enter>, <F1>

var_name [,var_name...]void main (void){ ...
}page 77

RN-BT-DATA-UG

RECOMMENDED READING
This user’s guide describes how to configure Roving Networks Bluetooth data modules.
The module-specific data sheets contain current information on the module hardware
specifications. Other useful documents are listed below. The following documents areavailable and recommended as supplemental reference resources:

RN41/41N Class 1 Bluetooth Module Data SheetThis data sheet provides detailed specifications for the RN41/41N module.

RN42/42N Class 2 Bluetooth Module Data SheetThis data sheet provides detailed specifications for the RN42/42N module.
To obtain any of these documents, visit the Roving Networks web site atwww.rovingnetworks.com.

DOCUMENT REVISION HISTORY
Revision 1.0r (March 2012)
This is the initial released version of the document.

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Index
Numerics

C

7-bit data mode ........................................................ 50

C,.............................................................................. 33
cable replacement.................................................... 57
using hardware ................................................. 57
using software................................................... 57
CF, ........................................................................... 33
COM port, changing ................................................. 50
commandaction ................................................................ 72
get ..................................................................... 72
quick reference ................................................. 71
set ..................................................................... 71
command mode ................................................... 6, 60
entering ............................................................... 8command syntax ...................................................... 19
commands
action ................................................................ 32
change .............................................................. 32
get ..................................................................... 31
GPIO ........................................................... 32, 73
set ..................................................................... 19
common issues ........................................................ 50
computerpairing ............................................................... 15
configuration............................................................. 11
local..................................................................... 7
over Bluetooth..................................................... 7
profile ................................................................ 60
remote................................................................. 7
serial adapter .................................................... 52
timer settings..................................................... 44
using GPIO ....................................................... 11
connecting................................................................ 15
connection
auto ................................................................... 52
changing COM port........................................... 50
example ............................................................ 51
issues connecting ............................................. 50
making .............................................................. 12
status ................................................................ 48
to multiple modules from 1 client ...................... 51
controlling modem.................................................... 47
CT,, .......................................................................... 33
Customer Support .................................................... 78

A
action command--- ...................................................................... 32& ....................................................................... 32+........................................................................ 32$$$ .................................................................... 32
C ....................................................................... 32
C, ...................................................................... 33
CF, .................................................................... 33
CFI .................................................................... 33
CFR .................................................................. 33
CT,, ................................................................... 33
F,1..................................................................... 34
H ....................................................................... 34
I,, ....................................................................... 34
IN, ..................................................................... 34
IR ...................................................................... 35
IS ...................................................................... 35
L ........................................................................ 35
M ....................................................................... 35
O ....................................................................... 36
P, ...................................................................... 36
Q ....................................................................... 36
R,1 .................................................................... 36
T,....................................................................... 36
U,, ..................................................................... 37
V ....................................................................... 37
W ...................................................................... 37
Z........................................................................ 37
action commands ..................................................... 72
Android phones ........................................................ 49
APL .......................................................................... 46
auto-connect ............................................................ 11
auto-connect ANY mode .......................................... 10
auto-connect DTR mode .......................................... 10
auto-connect master mode ...................................... 10
auto-connection ....................................................... 52
auto-discovery pairing .............................................. 11
auto-pairing .............................................................. 52

Bbaud rate .................................................................. 11
Bluetoothconfiguration ....................................................... 7
connection ...................................................12, 15
discovery........................................................... 13
pairing ............................................................... 13
profiles .............................................................. 60
boot-up, timing ......................................................... 69

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Ddata mode ............................................................ 6, 60
DB9 pins................................................................... 52
deep sleep................................................................ 42
default
pin code ............................................................ 17
default configuration................................................... 6
defaults, factory........................................................ 69

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design concerns ....................................................... 47
device reboot ........................................................... 36
dipswitch .................................................................. 54
dipswitch settings ..................................................... 54
dipswitches .........................................................11, 55
disable output drivers ............................................... 41
disabling output drivers ............................................ 43
discovery .................................................................. 13
example ............................................................ 51
HID profile ......................................................... 60
DUN-DCE ................................................................ 46
DUN-DTE ................................................................. 46

Eenable deep sleep.................................................... 41
evaluation boards....................................................... 5
examplediscovery and connection ................................. 51

Ffactory defaults......................................................... 69
factory reset ........................................................11, 47
firmware ................................................................... 75
fixes .............................................................75, 77
HID profile ......................................................... 60
release notes ...............................................75, 77
firmware version....................................................... 37
flag register bits........................................................ 61
flow control ............................................................... 53
flow control jumpers ................................................. 53

GPIO4 ................................................................ 12, 47
GPIO5 ................................................................ 12, 48
GPIO6 ...................................................................... 12
GPIO7 ...................................................................... 12
GPIO8 ................................................................ 12, 39
GPIO9 ................................................................ 12, 39
green LED ................................................................ 49

H
hardware connections .............................................. 48
hardware pairing ...................................................... 57
hardware signals ...................................................... 47
HCI mode ................................................................. 45
HCI over UART ................................................. 46
HCI over USB ................................................... 46
HID ........................................................................... 46
HID profile
discovery and pairing ........................................ 60
fag register ........................................................ 61
firmware ............................................................ 60
reports............................................................... 62translation ......................................................... 63
typical uses ....................................................... 59

II,, .............................................................................. 34
IN,............................................................................. 34
instant cable replacement ........................................ 57
IR.............................................................................. 35
IS.............................................................................. 35

G

J

get

jumpers .................................................................... 53
jumpers, flow control ................................................ 53

D ....................................................................... 31
E ....................................................................... 31
G ....................................................................... 32
G&..................................................................... 31
GB..................................................................... 31
GF ..................................................................... 31
GK..................................................................... 31
GR .................................................................... 31
get commands ......................................................... 72
GPIO assignments ................................................... 12
GPIO command
S^,..................................................................... 38
S@,................................................................... 37
S*, ..................................................................... 38
S&, .................................................................... 38
S%, ................................................................... 38
GPIO commands ..................................................... 37
GPIO pin power-up values ....................................... 38
GPIO pins ...........................................................11, 47
GPIO10 ...............................................................12, 39
GPIO11 ...............................................................12, 39
GPIO2 .................................................................12, 48
GPIO3 ...................................................................... 12

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K
K,.............................................................................. 35
kill command ............................................................ 35

Llatency, optimizing for .............................................. 49LEDstatus ................................................................ 49
local configuration ...................................................... 7lower transmit power ................................................ 41
lowering transmit power ........................................... 41
low-power mode....................................................... 41

Mmanaging power....................................................... 41
master mode ............................................................ 10
MDM SPP ................................................................ 46
microprocessor
interfacing with .................................................. 45
mode
7-bit data ........................................................... 50
auto-connect ANY............................................. 10

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auto-connect DTR............................................. 10
auto-connect master ......................................... 10
command .......................................................6, 60
data ................................................................6, 60
HCI.................................................................... 45
master ............................................................... 10
security ............................................................. 17
slave ................................................................. 10
trigger................................................................ 10
modem control ......................................................... 47
modes ...................................................................... 60

Nnull model jumpers ................................................... 53
null modem .............................................................. 53

O
operating modes
mode
operating.................................................... 10
operational modes ................................................... 60
optimizations ............................................................ 49
optimize inquiry and page window ........................... 41

P
pairing ...................................................................... 13
auto ................................................................... 52
hardware ........................................................... 57
HID profile ......................................................... 60
software ............................................................ 57
with computer ................................................... 15with smartphone ............................................... 15
pairing mode
mode
pairing ........................................................ 10
pin code, default....................................................... 17
power ....................................................................... 48
power consumption, reducing .................................. 41
power management ................................................. 41
power setting............................................................ 43
power settings .......................................................... 27
profileAPL ................................................................... 46
configuration ..................................................... 60
DUN-DCE ......................................................... 46
DUN-DTE.......................................................... 46
MDM SPP ......................................................... 46
override ............................................................. 61
settings ............................................................. 46
SPP................................................................... 46
profile values ............................................................ 29
profiue
HID.................................................................... 46

Q
quick reference ........................................................ 71

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R
Reading, Recommended ......................................... 78
reference designs....................................................... 5
release notes...................................................... 75, 77
replacement, cable................................................... 57
reports ...................................................................... 62
reset circuit............................................................... 47
revision history ......................................................... 75

S
security modes ......................................................... 17
serial adapter configuration...................................... 52
serial cableconfiguration ....................................................... 7
set
S-, ..................................................................... 29
S?,..................................................................... 30
S|,...................................................................... 30
S$,..................................................................... 30
S7,..................................................................... 19
SA, .................................................................... 19
SB, .................................................................... 20
SC, .................................................................... 20
SD, .................................................................... 21
SE, .................................................................... 21
SF,1 .................................................................. 22
SH, .................................................................... 22
SI,...................................................................... 23
SJ,..................................................................... 23
SL,..................................................................... 23
SM,.................................................................... 24
SN, .................................................................... 24
SO,.................................................................... 24
SP, .................................................................... 25
SQ,.................................................................... 25
SR, .................................................................... 25
SS, .................................................................... 26
ST, .................................................................... 26
SU, .................................................................... 26
SW, ................................................................... 26
SX, .................................................................... 27
SY, .................................................................... 27
SZ, .................................................................... 28
set commands.................................................... 19, 71
setitngs
dipswitch ........................................................... 54
setting
dipswitches ....................................................... 54
power ................................................................ 43
setting, switches....................................................... 57
slave mode............................................................... 10
smartphonepairing ............................................................... 15
sniff mode........................................................... 41, 42
software pairing........................................................ 57

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SPI bus .................................................................... 48
SPP .......................................................................... 46
switch settings.......................................................... 57
switches ..............................................................11, 54
SY, command .......................................................... 43Tthroughput, optimizing for ........................................ 49
timer
configuration settings ........................................ 44
used to lower power.......................................... 41
timing values ............................................................ 69translate HID to ASCII.............................................. 63transmit power
deep sleep ........................................................ 42
disabling output drivers ..................................... 43
lowering ............................................................ 43
reducing ............................................................ 41
sniff mode ......................................................... 42
trigger mode ............................................................. 10Uupgrading
via SPI .............................................................. 48
USB cable
configuration ....................................................... 7
using switches.......................................................... 11W
Warranty Registration .............................................. 78

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Version 0.02 3/26/13
Confidential - Preliminary Releasepage 82

RN-BT-DATA-UG

www.rovingnetworks.com

Version 0.02 3/26/13
Confidential - Preliminary Releasepage 83