2 ms·
There is a lot of documentation about the Alto. Are there also complete circuit diagrams? I am just curious because the processor was made in TTL at a time befo
by progman 10y ago
There is a lot of documentation about the Alto. Are there also complete circuit diagrams? I am just curious because the processor was made in TTL at a time before the 6502 and Z80 were born.
Sooner or later the last functional Xerox Alto will cease to work (sadly). In that case it could make sense to replace the dysfunctional parts with modern retro circuits. I wonder if a project to build a functional Alto clone (with TFT as screen) would make less effort than the famous monster 6502 which was presented recently.
- abritinthebay 10y agoAs it's a TTL (with 4 74181 MSI chips) wouldn't it be possible to just grok it from the circuit board..?
- orionblastar 10y agoI'm sure if they can make an adapter to use SIMM or DIMM RAM chips and bypass the bad memory chips. Use a SDCard instead of hard drives to store the OS and programs on. I guess someone could just write an emulator for the Raspberry PI and Linux or something based on the design of the Xerox Alto and how the chips function. It seems there are emulators or simulators for Xerox Alto out there already: http://toastytech.com/guis/salto.html http://toastytech.com/guis/salto.html http://altogether.brouhaha.com/ http://altogether.brouhaha.com/ To help out would be the source code to the Xerox Alto: http://www.computerhistory.org/collections/catalog/102706061 http://www.computerhistory.org/collections/catalog/102706061 It was released and I am sure the team can make modifications to it to make it run with modern retro hardware.
- kens 10y agoAll the Alto schematics are available at Al Kossow's Bitsavers [1]. If you want to understand how it works, start with the hardware manual [2]. The Alto processor could probably be kept running indefinitely, since it uses standard parts that can be replaced. The monitor is more difficult; the Living Computer Museum made some new monitor boards for their Altos, cloning the existing boards. The disk drives are another potential maintenance nightmare; I wonder if it would be possible to build a flash-based disk emulator. Making a FPGA-based Alto clone would be a possibility. [1] http://bitsavers.org/pdf/xerox/alto/schematics http://bitsavers.org/pdf/xerox/alto/schematics [2] http://bitsavers.org/pdf/xerox/alto/AltoHWRef.part1.pdf http://bitsavers.org/pdf/xerox/alto/AltoHWRef.part1.pdf
- Aloha 10y agoLCM built MASSBUS adapters for their PDP-10's, its probably possible. (to be clear, the ALTO was built in total from COTS parts, the disks are of a known type used on many other minicomputers, including I believe the DG NOVA)
- progman 10y agoThanks to all the posters here for their answers and recommendations!