psfSep 26, 2025

Here is the source code for my recent #TinyBasic and #MailStation work

https://gitlab.cs.washington.edu/fidelp/mailstation_apps

  • Machine code monitor and TinyBasic for Cidco MailStation (#z80 Internet Appliance)
  • The programs are small enough that a determined person can key them into the MailStation's built-in hex editor in 1 hour or less.   They run as loadable MailStation "channels".   They make it pretty fun as a self-contained mobile development platform, though you can't easily save your work. Carry pencil and paper!

https://gitlab.cs.washington.edu/fidelp/tinybasic

Show threadpsf
Pushed a small change to make tinybasic's assembly format compatible with #pasmo. (This did not require sacrificing compatibility with nongnu z80asm.)
Oct 3 at 2:27amWeb
Show threadpsfOct 4

The #pasmo assembler has this really neat feature where it'll accept #z80 opcodes and then do its best to emit equivalent #Intel8086 instructions. Effectively, this is the "assembly-level" forward compatibility that Intel advertised for migrating code from 8080 to 8086.

It certainly isn't perfect - a few instructions are unimplemented and have to be manually fixed, and I'm not sure I've caught all the subtle bugs where flags behave differently ... but, here's Palo Alto TinyBasic running on #MartyPC under DOS, in only a few hours work!

#retrocomputing #basic #TinyBasic

Show threadpsfOct 4

This #TinyBasic port also runs successfully on the #HP200LX palmtop. It wound up as a 2,799 byte .COM file. Added the ability to LOAD and SAVE the program source, and BYE to quit the interpreter.

Source and a prebuilt COM file here, if you would like to try on your own hardware.
https://gitlab.cs.washington.edu/fidelp/tinybasic
Careful, it may still have bugs!