Project phase one results

Our research was long and laborious. When the results of our information gathering started to become clearer, we discovered that it was not appropriate to offer up any one particular token computer hardware platform.

A ** Mike Bauer’s DREAM 6800.

Please see the README of this project’s previous phase.

B ** Permacomputers derived from popular microcontroller kits. See ulisp.

This particular course of action would require:

• a text editor
• a telnet client
• a gopher browser

All this software will be run over serial at first, and then the perpetually thorny topic of video out can be tackled later.

(Will video displays of the solarpunk post-apocalypse future even mostly support composite out?)

See this fedi discussion.

And this earlier one too.

C ** The EDUC-8 PDP-8 clone.

See here.

Also this fediverse post.

D ** A minimalistic serial-only 6502 homebrew platform

This proof-of-concept design is perfect for an ultra-simple and easily-constructed computer.

This is the memory map:

Address - Component
$0000-$3FFF - RAM (16KB)
$4200-$4203 - ACIA
$6000-$600F - VIA
$8000-$FFFF - ROM (32KB)

The benefits of this design are many:

• It uses a 6502, not the relatively exotic 6800
• Will easily run FORTH and BASIC
• Much easier and simpler memory addressing logic
• Quite a luxurious amount of ROM, and this presents a good opportunity to pack it full of interesting things, such as FORTH words, BASIC variants with larger ROM footprints…
• Possesses serial through the ACIA chip

However the following things are removed from the DREAM6800 design:

• Before was planned a simple hex keyboard. this new design must communicate through serial only.
• No composite video out. One of the great benefits of the DREAM6800 design was its relatively simple DMA video out circuitry. A lot of extra work is going to have to be done in order to give this design composite video out. This also means a serial terminal will be needed at all times in order to run this new 6502 design.
• The virtual machine that ran on the DREAM6800, the CHIP-8 will not be included in this design.

The new even simpler design is a clear victor in the comparison between the old and the new.

• People are unlikely to be able to quickly understand the DREAM6800 design software-wise, due to the 6800 ISA being far less well understood in the community. the 6502 guarantees a well understood and loved ISA. It makes the design more attractive to others.

• Composite out may not necessarily be the best option for video for a permacomputer. The project will actually need to do research in order to find out what will work best long-term.

• Although the CHIP-8 virtual machine instruction set is simpler to write on paper, higher level languages like FORTH and BASIC are more likely to be better preserved in the far future.

  See this fedi reference.