SEGA SATURN TECHNICAL BULLETIN # 4 6(PRELIMINARY)
To:

Sega and Third Party Developers

From:

Developer Technical Support

Date:

July 10, 1996

Re:

Data Cartridge Manual Ver.1.00

1Overview
1) Data cartridges
This data cartridge is a ROM cartridge for data that uses the A paththat supplements memory when the main memory is insufficient.
Its address appears in the A-Bus CS0 (22000000H) area.
2) Restrictions on Use
Data cartridges must contain only data; placing program code inthem is prohibited, regardless of whether the code is executed
directly or executed after transfer.
Placing program code in cartridges can be made into a security holeby creating a ROM with this portion rewritten. In future versions ofSaturn, it will no longer be possible to access the contents of thecartridge, so be sure to follow this rule.
3) Corresponding peripheral
The peripheral that corresponds to the SYSTEM ID of the CD-ROM
has an "R" added.

Example: Using a Sega Saturn standard pad with a data cartridge"JR∆∆∆∆∆∆∆∆∆∆∆∆∆∆" "∆" = space (20H)
Reference: Programmer's Guide, Vol. 1, Disk Format Standards Specification, section 4, "Boot System," p. 28.

2Data Cartridge System IDs
The following describes the system ID for data cartridges for SegaSaturn. Data cartridge system IDs and CD-ROM system IDs do not havethe exact same items. The data cartridge has some unique items, andsome other items require a different entry than on a CD-ROM, even forthe same item name. For that reason, when entering the system ID ofthe data cartridge, be sure to check this specification for all items.

3Structure of the System ID
012345600H Hardware ID
10H Manufacture ID
20H Product number
30H Release date40H Compatible area codes
50H RESERVED*160H Game title
70H
80H90H
A0H
B0H
C0H
D0H RESERVED
E0H RESERVEDCHECK SUM
F0H RESERVED

4789ABCDEFVersionDevice invoice
Back-up RAM information

RESERVED

Cautions on Notation
Rules
Usable characters
All characters usable in system IDs are ASCII code en-sizedalphanumeric characters. In some items, commas (,), slashes (/),
hyphens (-), and colons (:) may be used.

Entry••All entry is flush left unless otherwise indicated. Do not start
entries with spaces.
All open areas are ASCII code 20H unless otherwise indicated.

Definition of expressions

The ∆ sign and the word "space" used in the explanation indicate
ASCII code 20H. Also, em-size characters are used in this manual forgreater legibility.

Other definitions
Always fill in RESERVED areas with 00H.
*1 Fill in this area with spaces (20H).

5Explanation of Individual Items• Hardware ID (start address 00H)
Definition
Enter the unique data cartridge ID
Usable characters Capital letters onlyNo. of characters 16 characters
Entry rules
Always enter "SEGASATURN∆DATA∆"• Manufacturer ID (start address: 10H)
Definition
Enter the manufacturer name specified bySega.

Usable characters Alphanumeric characters only.
No. of characters 16 characters
Entry rules
For the Sega brand, enter the 16 characters"SEGA∆ENTERPRISES".
For licensees, enter the 16 characters"SEGA∆TP∆KAISHA-A". For "KAISHA-A",
enter the unique company code assigned tothe licensee. For example, the underlined
portion ofSEGA∆TP∆T-999∆∆∆is the company code, with the remainder
filled out by spaces. Be sure to enter 16characters.
• Product number (start address: 20H)
Definition
Enter the product number specified by SEGA.
Usable characters Alphanumeric characters only.
No. of characters 10 characters
Entry rules
Fill out the blank area with spaces.
Example of entry For Sega brand titles: "GS-9099∆∆∆"For licensee titles: T-99901G∆∆
Note: The remainder must be filled out withspaces to reach 10 characters.
• Version (start address: 2AH)
Definition
Enter the version number of the data
cartridge.
Usable characters Capital "V", numerals, and periods (.)
No. of characters 6 characters
Entry rules
Start with V followed by one numeral, aperiod, then three more numerals. The
release version is V1.000, with the version
number increasing every time thereafter theversion changes.
Example of entry For sample ROM: V0.802
For master ROM: V1.000
For version upgrade: V2.011*1The version number does not necessarily end with a masterrelease of V1.000. Additions and changes after release requirethat the version number also be updated.
*2This version number is different from the CD-ROM's version
number.
• Release date (start address: 30H)
Definition
Enter the date that the master ROM wascreated.
Usable characters Numerals only.
No. of characters 8 charactersEntry rules

Enter the year, month and day. Enter four
digits for the year and two digits each formonth and day.
Example of entry For January 23, 1996: "19960123"• Device information (start address: 38H)
Definition
Device information of the data cartridge.
Enter the device type and the capacity.
Usable characters En-size alphanumeric characters and spaces
No. of characters 8 characters
Entry rules
Devices are one capital letter, flush left.
Capacity is in Mbits indicated by threenumerals flush right. Fill in blanks withspaces.
Example of entry For a single 16 Mbit ROM: "R∆16∆∆∆∆"For an 8 Mbit ROM with a 4 Mbit SRAM:"R∆∆8S∆∆4"
List of devices
R: ROM
S: SRAM
D: DRAM
F: FRAM• Corresponding peripheral (start address: 40H)
Definition
Enter the area symbol for the region where
the application is to run.
Usable characters Only the capital letters specified in the list ofarea symbols below.
No. of characters 10 characters
Entry rules
Multiple symbols may be entered. Whenmultiple symbols are used, enter them flush
against each other without delimiting themwith commas or spaces. Fill in blanks withspaces.
List of area symbols
J: Japan
T: Asian NTSC (Taiwan, Philippines, Korea)
U: North America (USA, Canada), Centraland South American NTSC (Brasil)
E: European PAL, Southeast Asian PAL,Central and South American PAL
Example of entry For an application that will run in Japan,
Taiwan and Korea: "JT∆∆∆∆∆∆∆∆"• Back-up RAM information (start address: 4AH)
Definition
Enter device information of backup RAM
Usable characters En-size alphanumeric characters
No. of characters 6 charactersEntry rules

For cartridge software, when backup RAM isloaded into the same data cartridge. Enter
three en-size numerals (decimal) + the unit
+ a space + the access method for a total of sixcharacters.
• Unit symbols
Megabits" "M"
Kilobits: "K"• Access method symbols
In byte units with odd addresses: "O"
In byte units with even addresses: "E"In word units: "W"
When backup RAM is not used, enter spaces
for all six characters.
Example of entry Backup not used: "∆∆∆∆∆∆"64 Kb odd addresses: "064K∆O"
256 Kb even addresses: "256K∆E"
1 Mb both addresses: "001M∆W"• Game name (start address: 60H)
Definition
Enter the name of the game.
Usable characters Alphanumeric characters only. Spaces may
be used within game names. When multiple
titles are arrayed, delimit the titles withslashes (/), hyphens (-), or colons (:).
No. of characters 112 characters
Entry rules
When names vary in different sales regions,the different title names may be arrayed.
There are not a detailed set of rules for
multiple entry, but the titles should bediscernible from viewing this section. Fill inblanks with spaces.
Example of entry For multiple titles:
Example 1: "TITLE1/TITLE2"
Example 2: "J:TITLE1∆∆U:TITLE2"
Note: Fill in blanks completely with spaces(20H).
• Checksum (start address: E4H)
Definition
Enter the check sum for the data cartridge.
Usable characters Binary values
No. of characters 8 characters
Entry rules
8 digits of hexadecimal (32 bit length)
Example of entry A13B04F3H
See item 4) under "Check Procedure" for information on how to
calculate these.

6Access Methods
When booting up from a CD, initialize the hardware and then do thefollowing checks on the data cartridge. The application does thesechecks by checking the contents of the items of the system ID statedwithin the data cartridge. When an error occurs in the check, an error
message is displayed and the program halts.

Note:

Perform the following checks while the program is stopped. When doing these checks, be sure to move to themultiplayer screen.
1) Software reset (ABC + start)
2) Hardware reset
3) Tray open

Error Message:"The data cartridge is not inserted correctly. Turn off the power and reinsert the cartridge."• The attachment shows a sample display layout.
Check Procedure:The address of the data cartridge appears in the A-Bus CS0 (22000000H)
area. In the following explanation, this address is described as the offsetvalue.
1) Check the "SEGASATURN∆DATA∆" in data cartridge's hardware
ID (+00H).
2) Check the manufacturer ID (+10H), product number (+20H), andcorresponding peripheral (40H).
3) Set the SCU's wait.
A 150 ns ROM is used, so three clocks are needed and 13301FF0H
should be set in the A-Bus setting register (25FE00B0H).
Note: CS1 should be left at the 1FF0H set in the BOOT ROM.
Reference: See Hardware Manual, Vol. 1, SCU Users Manual, "ABus Setting Register," P.13.
4) Calculating the data cartridge's checksum
The calculation method adds integers from the data cartridge
address +100H to the end in 16 bit units and uses the final 32 bits asthe checksum. The value calculated is compared to the checksum(+E4H) in the data cartridge's system ID.
Note: +000H to +0FFH falls within the system ID area, so it is not partof the calculation.
5) If the above checks are all okay, check the backup RAM and movecontrol to the game program. There are no particular restrictions on
any access after this point. Be sure to always obey the injunction inparagraph (2), "Restrictions on Use," of section 1, "Overview."

0102030

01020The data cartridge
is not inserted
correctly.
Turn off the power
and re-insert thecartridge.

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