Retrocomputing

E2R16v2.1 - 27C400/800/160/322 programming adapter for Minipro TL866

E2R16 V21The Minipro TL866 is very popular among hobbyist because of its low price and ease of use. Its list of supported chips is however somewhat limited compared to more expensive professional programmers. The E2R16v2 adapter adds support for the ROM pinout compatible EPROM of the 27C400/800/160 and C322 series.

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RAMGS/8 - small form factor 8MB memory expansion for the Apple IIgs

ramgsThe apple IIgs is the most advanced computer in the Apple II series. Equipped with a 65c816 8/16-bit CPU with 24-bit address space it could address up to 16MB of memory. The original rom 01 model shipped with 256KB of fast RAM, the revised rom 3 shipped with 1MB (both had an additional 128KB of standard RAM and 64KB of sound RAM). RAMGS is a newly designed 8MB expansion card for this great classic computer.

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GGLABS Memory Test V0.33

GMT welcome screenGMT (GGLABS Memory Test) is a new developed memory test for the Apple IIgs optimized for speed and coverage. The code is based on the test algorithms described in "Testing Semiconductor Memories: Theory and Practice" by A.J. van de Goor. The program is mostly in C plus small sections in assembly. It is free software and released under the GPL v3 license.

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GRAM/1D - 1MB geoRAM clone for Commodore 64/128

geoRAMThe geoRAM is a 512KB memory expansion for the Commodore 64 and 128 designed by Berkeley Softworks for use with GEOS. While not as fast as the Commodore REU due to its lack of DMA capabilities, it still provides a significant performance boost. GRAM/1D is a 1MB geoRAM compatible cartridge based on a two 1Mx4 DRAM devices.

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GRAM/1D-C00 - 1MB geoRAM clone for Commodore 64/128

A new version of this project is available here

geoRAMThe geoRAM is a 512KB memory expansion for the Commodore 64 and 128 designed by Berkeley Softworks for use with GEOS. While not as fast as the Commodore REU due to its lack of DMA capabilities, it still provides a significant performance boost. GRAM/1D is a 1MB geoRAM compatible cartridge based on a two 1Mx4 DRAM devices.

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E2R16v2 - 27C400/800/160 programming adaptor for Minipro TL866

A new version of this project is available here

E2R16 V2The Minipro TL866 is very popular among hobbyist because of its low price and ease of use. Its list of supported chips is however somewhat limited compared to more expensive professional programmers. The E2R16v2 adapter adds support for the ROM pinout compatible EPROM of the 27C400/800/160 and C322 series.

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Retrochallenge 2017/10

geoRAMThis year our staff decided to enter the retrochallenge competition. Our goal is to reverse engineer the Berkely softworks geoRAM and publish what we discover under the GPL. The geoRAM is a 512KB memory expansion for the Commodore 64 and 128. Unlike the Commodore 1750 REU, which contain a custom chip, the geoRAM is built completely out of standard TTL chips.

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GLINKUSB-LT - User Port RS232 to USB for Commodore 8-bit Computers

glinkusbGLINKUSB-LT is a modern variation of the Commodore VIC-1011. Instead of providing a legacy 12V RS232 connection, it provides a USB Virtual Com Port (VCP) suitable for direct connection to any modern PC. The adapter is fully supported by the standard Commodore BASIC at up to 2400 baud. Jumpers allow the card to be configured as a UP9600 for 9600 baud operation in Novaterm and Striketerm. A reset button is also provided for added convenience.

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F2R16 - Flash based ROM Replacement for Amiga Computers

F2R16The Amiga, like many other computers of the late 80s, uses 16-bit wide mask ROMs to store the machine firmware. Unfortunately, the pinout of these ROMs is incompatible with the JEDEC defined EPROM pinout. Memory manufacturers produced "ROM compatible" EPROMS like the 27C400 to allow development and quick turn manufacturing. These EPROMS are however becoming quite hard to find and still require a UV lamp to erase the chips. F2R16 brings all the benefits of modern flash memory technology to any platform designed to use these obsolete devices.

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MACSIMM - Programmable ROM SIMM for Mac SE/30, IIfx and IIsi

MACSIMMThe Mac SE/30 was the fastest of the classic compact black and white Macintosh computers. It featured a 16MHz 68030 with 68882 FPU and a 32-bit memory interface and supported, albeit not officially, up to 128MB of RAM. Unfortunately the SE/30 ROM contained some old code that used 24-bit addressing making it 32-bit dirty. Many classic computer enthusiasts make their SE/30 32-bit clean by installing a Mac IIsi ROM SIMM. These are nowadays quite rare and difficult to find.

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