ATARI SXEGS Cartridge

Cartridge board and Housing for ATARI 65XE/130XE/800XE/XEGS/1200XL/800XL/600XL/800/400 8-bit computers based on SST39SF040 CMOS multi-purpose Flash memory chip.

• This is a S/XEGS type cartridge that allows you to store and run dozens of games.
• The project does not use programmable logic chips such as GAL-chips.
• Only conventional logic chips are used, such as 74LS00N, 74LS74N and 74LS374N.
• In the process of manufacturing a cartridge, microchips of Russian production can be used, such as ЭКР1533ИР23, К555ТМ2, К555ЛА3 etc.

The ROM files for the cartridge are created from the XEX files using the CreaXin1 utility, and then merged using the XEGS Merger to combine four files into one, forming a total of 512 kb of ROM memory.

The cartridge body consists of two 3D-printed parts. The parts connect to each other without the use of screws or glue.

Files:

• XEGS Cartridge_2022-11-28.zip - archive with Gerber files for PCB manufacturing
• ATARI-Cartridge-v3-Body.stl - 3D-model of cartridge housing body
• ATARI-Cartridge-v3-Cover.stl - 3D-model of cartridge housing cover

Ready to order project on PCBWay here

The following DIP chips are required to build a cartridge:

• SST39SF040 DIP32 (or other JEDEC standard ROM) (1pcs)
• 74LS374N (or ЭКР1533ИР23) DIP20 (1pcs)
• 74LS74N (or К555ТМ2) DIP14 (1pcs)
• 74LS00N (or К555ЛА3) DIP14 (1pcs)

And the following SMD 1206 parts are required to build a cartridge:

• 100 nF capacitors (3 pcs)
• 6.8 uF capacitor (1 pcs)
• 11 kOhm resistors (6 pcs)
• 3.3 kOhm resistor (1 pcs)

Optional: Round Hole IC Socket Connector DIP32 (1pcs) for SST39SF040.

And you need the ability to program the SST39SF040 Flash ROM, of course. Some sort of programmer like TL866II, or something else.

To make a cartridge body, you need the ability to print models on a 3D printer. The model of the cartridge case and its cover is attached.

When assembling the case, no additional fasteners, screws or glue are required. The case cover simply snaps into the body of the case, securing the PCB.

Instructions for creating a binary firmware file to flash in SST39SF040:

1. Download CreaXin1 and XEGS Merger utilities.
2. Use 'Creaxin1.exe' utility to create 128 kB image file. Add XEX files to fill 128 kB ROM space and save as 'Xin1 SXEGS cartridge ROM' file.
3. Repeat step 2 four times to create four 128 kB images with different XEXs.
4. Use 'XEGS merger.exe' utility to merge four 128 kB images into one 512 kB image. Add four 128 kB ROM images, choose 512 kB FLASH SIZE and press 'Create' button. Enter name of the new SXEGS ROM file and save it.
5. Flash 512 kB ROM image into SST39SF040. Erase ROM chip, write image and verify it.
6. Place the written chip in round hole IC socket or solder it into PCB.

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