Author Topic: SEGA SMS/GG Firmware (BETA)  (Read 62 times)

Offline skaman

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SEGA SMS/GG Firmware (BETA)
« on: 10/Dec/2017 03:41:40 AM »
I've been working on a new firmware for Sega Master System and Game Gear carts.

I added improved cart recognition and SRAM save support.  I also added proper Codemasters cart support.  The SMS/GG Plugin needs to be modified for the Codemasters carts to work.

As part of the development, I made a working prototype Mark III Plugin.  The plugin allows you to read Japanese Mark III carts and Sega Card/My Cards with a Card Catcher (see http://forum.retrode.org/index.php/topic,368.msg2711.html#msg2711).

Here's a summary:
Code: [Select]
v0.24b beta (2017-12-09)
- Changes by skaman:
-- SEGA SMS and GG Saves!
-- Fixed SMS SRAM read support.
-- Added SMS SRAM write support.
-- SMS SRAM carts should be identified by Product Code
   and display the .SAV file.  The .SAV file can be read
   and written.
-- Corrected the ROM size identification for Mega,
   Two-Mega, and Four-Mega carts.
-- Fixed Product Code identification.
-- Fixed identification of SMS Monopoly (U) to output
   the proper ROM and SRAM save file.
-- Fixed identification of SMS Wonder Boy in Monster
   World (EK) and SMS New Zealand Story (E) to output the
   proper ROM file.
-- Added code to improve handing carts with bad headers.
   A small number of games will still require using the
   [forceSystem] setting in the Config file due to
   missing ASCII text at the start of the header.
-- Added identification of SMS Ys (J) save file.
-- Added identification of SMS Haja no Fuuin (J) save file.
-- Added GG SRAM save support.
-- GG SRAM carts should be identified by Product Code
   and display the .SAV file.  The .SAV file can be read
   and written.
-- Added identification of GG Pro Yakyuu '91 (J).
-- Fixed GG ROM size "0" identification.  ROM size "0"
   is 256KB, however, carts may be 256KB, 512KB, or 1MB.
-- Fixed SMS Codemasters cart detection.
-- Added GG Codemasters cart support.
-- WARNING:  Codemasters carts require modification of the
   SMS/GG Plugin.  The CLOCK connection must be made from
   both slots to the plugin edge (pin B9).  In addition,
   SMS Codemasters carts require the /MREQ pin to be
   connected to the /CE pin.
-- Moved SMS/GG cart detection ahead of NGP cart detection.
   Some SMS carts were incorrectly detected as NGP.
-- Changed the SMS/GG SRAM save extension to ".SAV".
   This appears to be the extension expected by most
   SEGA emulators.
« Last Edit: 10/Dec/2017 05:20:41 AM by skaman »

Offline skaman

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Re: SEGA SMS/GG Firmware (BETA)
« Reply #1 on: 10/Dec/2017 04:06:48 AM »
For Codemasters cart support, you need to:

1) Connect the CLOCK pin on each slot to the plugin edge pin B9.  For Game Gear, CLOCK is pin 40 and for Master System, CLOCK is pin 47.

2) Master System requires an additional connection for the /MREQ pin 3 to /CE pin 13.

3) Run BETA firmware v0.24b or higher.

Here are a couple pictures of the modified plugin: