Rertocomputing

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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CGA2RGB - Digital RGBI to analog RGB for Commodore 128 and IBM PC CGA

CGA2RGBThe 80 column output of the Commodore 128 is the same digital RGBI used by the original IBM CGA graphics adapter. Unfortunately nowadays is quite difficult to find a monitor with the suitable RGBI input. The CGA2RGB adapter will convert the TTL RGBI to analog RGB suitable to be connected directly to a 15KHz capable RGB monitor or to the popular Gonbes GBS-8200 VGA converter.

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CGA2RGB-A00 - Digital RGBI to analog RGB for Commodore 128 and IBM PC CGA

CGA2RGBThe 80 column output of the Commodore 128 is the same digital RGBI used by the original IBM CGA graphics adapter. Unfortunately nowadays is quite difficult to find a monitor with the suitable RGBI input. The CGA2RGB adapter will convert the TTL RGBI to analog RGB suitable to be connected directly to a 15KHz capable RGB monitor or to the popular Gonbes GBS-8200 VGA converter.

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GTERM25 - DB25 Active SCSI Terminator with diagnostics LEDs

GTERMActive termination is required to get newer higher performance drives working on vintage computers. Unfortunately both the Amiga and older Apple computers use a DB25 SCSI connector which makes finding a suitable terminator quite difficult. GTERM25 solves this problem providing a high performance active terminator with a DB25 connector and SCSI diagnostic LEDs.

RAMGS/4 - SIMM based 4MB 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/4 is a newly designed 4MB SIMM based memory expansion card for this great classic computer.

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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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RAMGS/8 - SIMM based 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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GTERM25-A00 - DB25 Active SCSI Terminator with diagnostics LEDs

A new version of this project is available here

GTERMActive termination is required to get newer higher performance drives working on vintage computers. Unfortunately both the Amiga and older Apple computers use a DB25 SCSI connector which makes finding a suitable terminator quite difficult. GTERM25 solves this problem providing a high performance active terminator with a DB25 connector and SCSI diagnostic LEDs.

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