ANR028
C ALYPSO T RANSPARENT M ODE
UART- TO -W I F I B RIDGEV ERSION 1.1
J ULY 19, 2023

WIRELESS CONNECTIVITY & SENSORS
ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge

Revision history
Manualversion

Notes

Date

1.0

• Initial version

January 2022

1.1

• Updated Important notes, meta data and document
style

July 2023

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge

Contents
1 Introduction

3

2 Functional description
2.1
Power save mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

45

3 Wi-Fi connection setup
3.1
Configure Wi-Fi via AT command interface . . . . . . . . . . . . . . . . . . . . .
3.1.1 AT+wlanConnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.2 AT+wlanProfileAdd . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2
Configure Wi-Fi via web interface . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1 Start in provisioning mode . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.2 Add WLAN profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7
7
7
7
8
8
8

4 Socket setup
4.1
Configure the socket settings via AT commands . . . . . . . . . . . . . . . . . .
4.1.1 Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2
Configure the socket settings via web interface . . . . . . . . . . . . . . . . . .

11
11
13
15

5 Data transmission
18
5.1
Configure the UART trigger settings via AT commands . . . . . . . . . . . . . . 18
5.2
Configure the UART trigger settings via web interface . . . . . . . . . . . . . . 19
6 Throughput

20

7 References

21

8 Important notes

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1 Introduction
The Calypso WLAN module developed by Würth Elektronik eiSos is intended to be used as aradio sub-system in order to provide WLAN (IEEE 802.11) communication capabilities to systems. The UART acts as the primary interface between the module and a host micro-controller.
The module can be fully configured and controlled using a set of AT-commands sent as messages via UART. Once configured, the module independently manages WLAN connectivity
allowing the host controller to utilize its resources for its application tasks.
Firmware version 2.0.0 of the radio module now supports the so-called "Transparent Mode"
mode of operation, which when chosen instead of the "AT commands mode", allows applications to utilize the module as a UART-to-WiFi bridge.
In transparent mode, the Calypso automatically connects to a pre-configured Wi-Fi accesspoint and opens a socket for communication with a preconfigured remote endpoint (TCP server,
TCP client or UDP endpoint). Afterwards, the Calypso acts as a transparent bridge between
the UART and the created socket. This means that all data sent to the Calypso via UART is
forwarded to the socket and all data received on the socket is output on the UART.

This application note gives a short overview of this new feature.

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge

2 Functional description
When booting the Calypso radio module, the voltage level of the pins APP_MODE_0 and
APP_MODE_1 is checked to detect the mode of operation. In case both pins have a high level,
the Calypso starts in transparent mode.
In transparent mode, the Calypso first tries to connect to a WiFi access point. In case this fails
due to the absence of the configured access point or wrong access point credentials, it retries
until a connection is established.
On success, the pin STATUS_IND_0 turns high and the Calypso tries to open a socket. In caseof failure, it retries until a socket has been opened.
As soon as a socket has been opened and the connection has been established successfully,
the pin STATUS_IND_1 turns high and the UART of the Calypso is switched on. All UART data
is forwarded to the socket and vice versa. In this state the pin /RTS of the Calypso indicateswhen the radio module is ready to receive data via UART. If the UART flow control is disabled,
the pin stays active (LOW) as long as a socket is available. In case the UART flow control isenabled, the /RTS pin stays active (LOW) as long as a socket is available and the UART isready to receive more data.

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge

Mode detection

Start

AT commandmode

AT command
operation
Interpret
AT commands

Transparent
mode

0

1

Connect to WiFi

FailedSuccess

0
WiFi disconnected1

Connect socket

FailedSuccess

0
Socket closed or
WiFi disconnected1

Forward UART data
to WiFi, and viceversa

Figure 1: Flow chart - transparent mode

Before starting the module in transparent mode, various settings have to be defined in order toensure successful WiFi connection and socket setup. For details regarding the required steps,
please refer to the following chapters.

2.1 Power save mode
For battery powered systems with a requirement that the devices always remain online (i.e.
connected to WiFi Network and socket but UART disabled), the Calypso offers a power savefeature. This feature allows significant power saving while staying connected to the Wi-Fi
network as well as sustaining an active connection. An average of less than 2 mA current
consumption is achieved in station mode with an active socket connection. This power savefeature is supported in the transparent mode, too. Steps to enable the power save feature aredescribed in chapter 4.
As the module’s UART RX is disabled in this state, the host is required to wake up the module5

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before sending data to it. Especially in power save mode, using UART flow control is recommended for any UART baudrate.
After a wake-up by the host (via WAKE-UP pin), it can send data and trigger transmission of
one radio packet. The module will go back to power save automatically after the radio packet
was sent. Another UART transfer from the host to the module must be preceded with a new
wakeup by the host.
If data is received on the radio side it will be forwarded on the UART to the host. During thatprocess, the host is not allowed to send data to the module.

The wakeup pin shall not be used during an active UART transfer from Calypso
to host.

When in power save mode, the Calypso is ready to receive data on the UART
10 ms after a rising edge on the WAKE-UP pin.

The on-board HTTP server will not be available in the power save mode.

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3 Wi-Fi connection setup
To successfully set up a connection to a WiFi access point, the user has to enter the network
credentials such as SSID, password and security mode into the Calypso in advance. There are
two ways of doing so:
1. Use the AT-commands interface to configure the Calypso via UART
2. Use the web interface to configure the module

3.1 Configure Wi-Fi via AT command interface
To enter the credentials of the access point via AT commands, the Calypso radio module must
be started in "AT command mode" by applying a low level at the pins APP_MODE_0 and
APP_MODE_1 during start-up.
If this has been done, the credentials can be added in two ways. Either to use the command
AT+wlanConnect to connect to an access point, or to use the command AT+wlanProfileAdd tosimply add the profile to the radio module (see user manual [1]).
Then the module automatically connects to one of the configured access points after device
reset, in case the WLAN connection policy is set to Auto (or Auto|Fast).
AT+wlanPolicySet=connection,Auto|Fast,

Code 1: Example AT+wlanPolicySet

The policy is automatically set to Auto|Fast when the module is started intransparent mode.

3.1.1 AT+wlanConnect
AT+wlanConnect=[SSID],[BSSID],[SecurityType],[SecurityKey],[SecurityExtUser],[
SecurityExtAnonUser],[SecurityExtEapMethod]

Code 2: AT+wlanConnect
AT+wlanConnect=mySSID,,WPA_WPA2,myPassword,,,

Code 3: Example AT+wlanConnect
3.1.2 AT+wlanProfileAdd
The command AT+wlanProfileAdd allows you to store up to seven preferred WLAN profiles
which you can use to specify multiple access points to be used in transparent mode. Eachprofile stores the access point credentials along with a profile priority, which determines theorder of connection.

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AT+wlanProfileAdd=[SSID],[BSSID],[SecurityType],[SecurityKey],[SecurityExtUser],[SecurityExtAnonUser],[SecurityExtEapMethod],[priority]

Code 4: AT+wlanProfileAdd
The following example adds a profile with the highest priority (15).
AT+wlanProfileAdd=mySSID,,WPA_WPA2,myPassword,,,,15

Code 5: Example AT+wlanProfileAdd

3.2 Configure Wi-Fi via web interface
To enable easy configuration when integrated into an embedded system with limited HMI capabilities, the Calypso offers a provisioning mode. In this mode, the module acts as an AP andallows external devices with appropriate credentials to connect and access the on-board HTTP
server. The user can conveniently browse the settings web page and configure the moduleusing any web browser.

The web pages for provisioning require JavaScript.

3.2.1 Start in provisioning mode
There are two ways to set the Calypso to provisioning mode.
1. When starting the module in AT command mode the command
AT+provisioningStart

starts the provisioning.
2. Alternatively, apply a LOW signal to the APP_MODE_0 pin, a HIGH signal to the APP_MODE_1
pin and restart the module.
When the provisioning mode has been started successfully, the LED at STATUS_IND_1 flashes
with an interval of 1 s. The module has created an access point with a SSID "calypso_" followedby the MAC of the module (example "calypso_CAFFEE123456"). Now any Wi-Fi enabled device can connect to the access point using WPA2 security and the key "calypsowlan".

3.2.2 Add WLAN profileOn the device connected to the Calypso AP, open the website "calypso.net" in a browser.

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Figure 2: Provisioning main page
To save a WLAN profile in the module, select the SSID from the dropdown menu or enter thesame manually in the text field. Check the correct security type, enter the key if necessary andclick on the "Add" button. A pop-up appears confirming the addition of the profile.

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Figure 3: Provisioning main page
In provisioning mode, the module is set to start as an AP. In order to start the module in stationmode, select "Station" in the "Device Mode" drop down menu and click on "Apply". Note that forthe module to connect to one of the stored profiles after a reset or when the connection is lost,the WLAN connection policy has to be set to Auto (or Auto|Fast). The policy is automatically
set to Auto|Fast when the module is started in transparent mode.

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge

4 Socket setup
In case the Calypso radio module has successfully set up a connection to an access point intransparent mode, the pin STATUS_IND_0 turns high. The next step is to open a socket.
The behavior of the module depends on the socket configuration:• In case the module is configured to use a UDP socket, the socket will open and datatransmission to the specified peer address can start immediately.
• In case the module is configured to use a TCP server socket, the Calypso radio module
waits for a TCP client to connect to it, before data transmission can start.
• In case the module is configured to use a TCP client socket, the Calypso tries to connect
to the TCP server at the specified peer address. As soon as the connection has been
established, data transmission can start.
To enable the successful setup of a socket, various settings must be defined in advance. There
are two ways of doing so:
1. Use the AT-commands interface to enter the socket settings via UART
2. Use the web interface to enter the socket settings

4.1 Configure the socket settings via AT commands
To enter the socket settings via AT commands, the Calypso radio module must be started in"AT command mode" by applying a low level at the pins APP_MODE_0 and APP_MODE_1
during start-up.
If this has been done, the socket type and information of the peer device can be specified using
the AT+set command:
AT+set=transparent_mode,[option],[value1]

Code 6: AT+set
Available options:• power_save: value1 determines whether the power save feature is activated or not (trueor false)• remote_address: value1 is the IP of the peer device• remote_port: value1 is the port of the peer device• local_port: value1 is the port of the Calypso (The local port must not be 80 or 8080.)• socket_type:– value1 is udp: send/receive data to/from a UDP device at remote_address and remote_port– value1 is tcp_server: create a TCP server on local_port and send/receive data
to/from the first peer device that connects

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge– value1 is tcp_client: create a TCP connection to a TCP server at remote_address
and remote_port and send/receive data to/from it• secure_method:– value1 is none: no encryption and authentication used
– value1 is sslv3: in case of a TCP socket, SSL v3 is used
– value1 is tlsv1: in case of a TCP socket, TLS v1 is used
– value1 is tlsv1_1: in case of a TCP socket, TLS v1.1 is used
– value1 is tlsv1_2: in case of a TCP socket, TLS v1.2 is used
– value1 is sslv3_tlsv1_2: in case of a TCP socket, the highest method between SSL
v3 and TLS v1.2 is used• skip_date_verify: value1 determines whether the date verification of the SSL certificate
is skipped (true or false). This setting is only applicable if the secure method is not "none"
and is useful if there is no SNTP server available in the network.
• disable_cert_store: value1 determines whether self-signed certificates should be accepted (true or false). This setting is only applicable if the secure method is not "none".
In case the parameter "secure_method" is not "none", additional parameters for the SNTP
server and SSL certificate must be specified before a secure socket can be setup.
The SNTP server address can be specified via the command AT+netappset:
AT+netappset=sntp_client,server_address,0,time.google.com

Code 7: Example AT+netappset
Furthermore, the private key, SSL certificate and SSL root CA must be stored in the file system.
To do so, the commands AT+fileOpen, AT+fileWrite and AT+fileClose must be used:
AT+fileOpen=[fileName],[options],[fileSize]
AT+fileWrite=[fileID],[offset],[format],[length],[data]
AT+fileClose=[fileID],[certificateFileName],[signature]

Code 8: Create a new file in file system
Depending on the file size, the use of multiple AT+fileWrite commands before
the AT+fileClose command may be required to transfer the entire file’s content
to the file system. It is recommended to use chunks of not more than 1024
bytes per AT+fileWrite command.
The files must be stored at the following predefined locations in the file system:
File

fileName

Private key

user/transparentmode_privatekey

SSL certificate

user/transparentmode_certificate

SSL root CA

user/transparentmode_rootca

Table 1: Pre-defined file names

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4.1.1 Examples/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,udp
AT+set=transparent_mode,secure_method,none/* set remote address */AT+set=transparent_mode,remote_address,192.178.168.22
AT+set=transparent_mode,remote_port,5001/* set local port */AT+set=transparent_mode,local_port,5001

Code 9: Example UDP socket configuration/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,tcp_client
AT+set=transparent_mode,secure_method,none/* set remote address */AT+set=transparent_mode,remote_address,192.178.168.22
AT+set=transparent_mode,remote_port,5001

Code 10: Example TCP client socket configuration/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,tcp_server
AT+set=transparent_mode,secure_method,none/* set local port */AT+set=transparent_mode,local_port,5001

Code 11: Example TCP server socket configuration/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,tcp_client
AT+set=transparent_mode,secure_method,sslv3_tlsv1_2/* set remote address */AT+set=transparent_mode,remote_address,192.178.168.22
AT+set=transparent_mode,remote_port,5001/* use SNTP server for certificate date verification */AT+netappset=sntp_client,server_address,0,time.google.com
AT+set=transparent_mode,skip_date_verify,false

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ANR028 - Calypso Transparent Mode UART-to-WiFi Bridge/* verifies public root CA */AT+set=transparent_mode,disable_cert_store,false

Code 12: Example SSL client socket configuration in network with internet access/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,tcp_client
AT+set=transparent_mode,secure_method,sslv3_tlsv1_2/* set remote address */AT+set=transparent_mode,remote_address,192.178.168.22
AT+set=transparent_mode,remote_port,5001/* disable certificate date verification */AT+set=transparent_mode,skip_date_verify,true/* use self signed certificate */AT+set=transparent_mode,disable_cert_store,true/* load root CA in file system */AT+fileOpen=user/transparentmode_rootca,CREATE|OVERWRITE,...
AT+fileWrite=...
AT+fileClose=...

Code 13: Example SSL client socket configuration in network without internet access/* enable power save feature */AT+set=transparent_mode,power_save,true/* set socket type */AT+set=transparent_mode,socket_type,tcp_server
AT+set=transparent_mode,secure_method,sslv3_tlsv1_2/* set local port */AT+set=transparent_mode,local_port,5001/* disable date verification as SNTP is not available */AT+set=transparent_mode,skip_date_verify,true/* use self signed certificate */AT+set=transparent_mode,disable_cert_store,true/* load private key in file system */AT+fileOpen=user/transparentmode_privatekey,CREATE|OVERWRITE,...
AT+fileWrite=...
AT+fileClose=...
/* load certificate in file system */AT+fileOpen=user/transparentmode_certificate,CREATE|OVERWRITE,...
AT+fileWrite=...
AT+fileClose=...

Code 14: Example SSL server socket configuration with self-signed certificate

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4.2 Configure the socket settings via web interface
In order to configure the socket settings of the module via web interface, the module needs
to be in provisioning mode. See chapter 3.2.1 for instructions on how to start the module’s
provisioning mode. Once in this mode, open the website "http://calypso.net/usersettings.html"
in a browser on the device connected to the Calypso AP.

This webpage uses RESTful APIs in order to perform GET and POST requests
on resources on the Calypso. A detailed description of these API calls can befound in chapter "The HTTP server interface" of the Calypso user manual [1].
This page offers two tabs to get and set the usersettings of the radio module. Perform thefollowing steps in order to configure the socket settings for transparent mode.
• Open the "SET" tab.
• Select "transparent_mode" from the category drop-down.
• Select the required setting from the "Setting" drop-down. For example, "socket_type".
• Select or enter the value for this setting. For example, "SOCKET_TYPE_TCP_SERVER".
• Click on the "POST" button to set the configuration.

Figure 4: Configure socket setting

Follow the examples described in chapter 4.1.1 to completely configure themodule’s socket settings in order to work in transparent mode.

In the "GET" tab, select the category and the setting drop-downs to read the current values.

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Figure 5: Read socket setting
The provisioning pages on the Calypso offer a possibility to upload certificates to the on-board
file system. In order to upload a file, open the homepage "http://calypso.net/file.html" and:• Click on the "File upload" option on the menu bar.
• Click on the "Choose file" button to open the file browser on the device.
• Browse and select the file to be uploaded.
• Click on "Upload file" to save the file on to the Calypso file system.
• All files are stored under the path "/user".

Figure 6: File upload

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Follow the examples described in chapter 4.1.1 to completely configure themodule’s socket settings in order to work in transparent mode.

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5 Data transmission
As soon as a socket has been opened successfully, the pin STATUS_IND_1 turns high. Now
data transmission can start. All data received on the socket will be sent via UART to the connected host controller. All data that is sent via UART to the Calypso radio module in transparent
mode will be forwarded to the socket.
The trigger that causes the Calypso radio module to forward the data to the socket can be
configured in the user settings of the module. There are two ways of setting the trigger:
1. Use the AT-commands interface to enter the UART trigger settings via UART
2. Use the web interface to enter the UART trigger settings

5.1 Configure the UART trigger settings via AT commands
To enter the UART trigger settings via AT commands, the Calypso radio module must be started
in "AT command mode" by applying a low level at the pins APP_MODE_0 and APP_MODE_1
during start-up.
If this has been done, the UART trigger settings can be specified using the AT+set command:
AT+set=UART,[option],[value1]

Code 15: AT+set
Available options:• transparent_trigger: value1 is a bitmask of the following options– timer: data is transmitted in transparent mode if a pause of at leasttransparent_timeout milliseconds is detected in the data stream– 1etx: data is transmitted in transparent mode if the ETX (first byte oftransparent_etx) character has been received by the Calypso– 2etx: data is transmitted in transparent mode if the full ETX (both bytes oftransparent_etx) has been received by the Calypso– transmit_etx: if this option is set and if 1etx or 2etx is used as trigger in transparent
mode, the ETX character is not removed from the data stream and is forwarded tothe socket• transparent_timeout: value1 is timeout (6-1000) [ms]• transparent_etx: value1 is 2 byte ETX in hexadecimal notation
AT+set=UART,transparent_trigger,2etx|timer
AT+set=UART,transparent_timeout,20
AT+set=UART,transparent_etx,0x0D0A

Code 16: Example Trigger on ETX 0x0D0A and after 20 ms
AT+set=UART,transparent_trigger,1etx|transmit_etx
AT+set=UART,transparent_etx,0x0D00

Code 17: Example Trigger on ETX 0x0D and forward ETX to socket

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5.2 Configure the UART trigger settings via web interface
In order to configure the UART trigger settings via the web interface, follow the steps describedin chapter 4.2 to access the usersettings page. Select the category "UART" and the setting"transparent_trigger", "transparent_timeout" or "transparent_etx" from the corresponding dropdowns to GET/SET the values.
This webpage uses RESTful APIs in order to perform GET and POST requests
on resources on the Calypso. A detailed description of these API calls can befound in chapter "The HTTP server interface" of the Calypso user manual [1].

Figure 7: Configure UART trigger setting

Figure 8: Read UART trigger setting

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6 Throughput
In any case, to gain highest throughput from host to socket data transmission, it is importantthat the Calypso is able to forward the payload data from UART to the socket in the most efficient way. To do so, the Calypso internally moves data chunks of variable size from UART to thesocket. The more data is received on the UART in a dedicated time frame, the smaller thesechunks are. Thus, the best chunk size and therefore the highest throughput can be reached byeither using a baud rate of about 921600 baud, or by adding a pause (about 10 ms, which is
on average the latency for Calypso to forward a UART frame to WiFi) after every 1460 bytes inthe data stream when using higher baud rates.

Baud rate[Baud]

Throughput[kByte/s]

92160049

Flow control enabled, "\r\n" as trigger, pause of 10 ms after
every 1460 Bytes

92160069.5

Flow control enabled, "\r\n" as trigger, 1460 Bytes without pause

2000000

78

Flow control enabled, "\r\n" as trigger, pause of 10 ms after
every 1460 Bytes

3000000

82

Flow control enabled, "\r\n" as trigger, pause of 10 ms after
every 1460 Bytes

Test condition

Table 2: Transparent mode - throughput examples

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7 References[1] Würth Elektronik. Calypso user manual. https://www.we-online.de/katalog/de/manual/
2610011025000.

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8 Important notes
The Application Note and its containing information ("Information") is based on Würth Elektronik eiSos GmbH & Co. KG and its subsidiaries and affiliates ("WE eiSos") knowledge andexperience of typical requirements concerning these areas. It serves as general guidance andshall not be construed as a commitment for the suitability for customer applications by WE
eiSos. While WE eiSos has used reasonable efforts to ensure the accuracy of the Information,
WE eiSos does not guarantee that the Information is error-free, nor makes any other representation, warranty or guarantee that the Information is completely accurate or up-to-date. The
Information is subject to change without notice. To the extent permitted by law, the Information
shall not be reproduced or copied without WE eiSos’ prior written permission. In any case,
the Information, in full or in parts, may not be altered, falsified or distorted nor be used for any
unauthorized purpose.
WE eiSos is not liable for application assistance of any kind. Customer may use WE eiSos’assistance and product recommendations for customer’s applications and design. No oral or
written Information given by WE eiSos or its distributors, agents or employees will operate tocreate any warranty or guarantee or vary any official documentation of the product e.g. data
sheets and user manuals towards customer and customer shall not rely on any provided Information. THE INFORMATION IS PROVIDED "AS IS". CUSTOMER ACKNOWLEDGES THATWE EISOS MAKES NO REPRESENTATIONS AND WARRANTIES OF ANY KIND RELATED
TO, BUT NOT LIMITED TO THE NON-INFRINGEMENT OF THIRD PARTIES’ INTELLECTUAL PROPERTY RIGHTS OR THE MERCHANTABILITY OR FITNESS FOR A PURPOSEOR USAGE. WE EISOS DOES NOT WARRANT OR REPRESENT THAT ANY LICENSE, EITHER EXPRESS OR IMPLIED, IS GRANTED UNDER ANY PATENT RIGHT, COPYRIGHT,
MASK WORK RIGHT, OR OTHER INTELLECTUAL PROPERTY RIGHT RELATING TO ANYCOMBINATION, MACHINE, OR PROCESS IN WHICH WE EISOS INFORMATION IS USED.
INFORMATION PUBLISHED BY WE EISOS REGARDING THIRD-PARTY PRODUCTS ORSERVICES DOES NOT CONSTITUTE A LICENSE FROM WE eiSos TO USE SUCH PRODUCTS OR SERVICES OR A WARRANTY OR ENDORSEMENT THEREOF.
The responsibility for the applicability and use of WE eiSos’ components in a particular customer design is always solely within the authority of the customer. Due to this fact it is up
to the customer to evaluate and investigate, where appropriate, and decide whether the device with the specific characteristics described in the specification is valid and suitable for therespective customer application or not. The technical specifications are stated in the current
data sheet and user manual of the component. Therefore the customers shall use the data
sheets and user manuals and are cautioned to verify that they are current. The data sheets
and user manuals can be downloaded at www.we-online.com. Customers shall strictly observe
any product-specific notes, cautions and warnings. WE eiSos reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products andservices at any time without notice.
WE eiSos will in no case be liable for customer’s use, or the results of the use, of the components or any accompanying written materials. IT IS CUSTOMER’S RESPONSIBILITY TO
VERIFY THE RESULTS OF THE USE OF THIS INFORMATION IN IT’S OWN PARTICULAR
ENGINEERING AND PRODUCT ENVIRONMENT AND CUSTOMER ASSUMES THE ENTIRERISK OF DOING SO OR FAILING TO DO SO. IN NO CASE WILL WE EISOS BE LIABLE FOR

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CUSTOMER’S USE, OR THE RESULTS OF IT’S USE OF THE COMPONENTS OR ANY ACCOMPANYING WRITTEN MATERIAL IF CUSTOMER TRANSLATES, ALTERS, ARRANGES,
TRANSFORMS, OR OTHERWISE MODIFIES THE INFORMATION IN ANY WAY, SHAPE OR
FORM.
If customer determines that the components are valid and suitable for a particular design andwants to order the corresponding components, customer acknowledges to minimize the risk ofloss and harm to individuals and bears the risk for failure leading to personal injury or death
due to customers usage of the components. The components have been designed and developed for usage in general electronic equipment only. The components are not authorized foruse in equipment where a higher safety standard and reliability standard is especially requiredor where a failure of the components is reasonably expected to cause severe personal injury
or death, unless WE eiSos and customer have executed an agreement specifically governing
such use. Moreover WE eiSos components are neither designed nor intended for use in areas
such as military, aerospace, aviation, nuclear control, submarine, transportation, transportation signal, disaster prevention, medical, public information network etc. WE eiSos must be
informed about the intent of such usage before the design-in stage. In addition, sufficient reliability evaluation checks for safety must be performed on every component which is used inelectrical circuits that require high safety and reliability functions or performance. COSTUMER
SHALL INDEMNIFY WE EISOS AGAINST ANY DAMAGES ARISING OUT OF THE USE OF
THE COMPONENTS IN SUCH SAFETY-CRITICAL APPLICATIONS.

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List of Figures
1
2
3
4
5
6
7
8

Flow chart - transparent mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Provisioning main page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Provisioning main page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configure socket setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Read socket setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
File upload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configure UART trigger setting . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Read UART trigger setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5
9
10
15
16
16
19
19

List of Tables
12Pre-defined file names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Transparent mode - throughput examples . . . . . . . . . . . . . . . . . . . . . . 20

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Contact
Würth Elektronik eiSos GmbH & Co. KG
Division Wireless Connectivity & Sensors
Max-Eyth-Straße 174638 Waldenburg
Germany
Tel.: +49 651 99355-0
Fax.: +49 651 99355-69
www.we-online.com/wireless-connectivity