We had great fun at the 2018 Atlanta Historical Computing Society Christmas Party turned Hackathon for the HP 4952A. After quite a bit of poking and prodding, BASIC-80 with a simple keymap was rendered working. Without a full understanding of the MMU and which banks are usable there was only just enough room to have shifted and unshifted keymaps working with the terribly hacked together keyboard routines. We however were able to stuff a few tiny programs in the 8KB of usable memory while playing around and letting folks try their hand at typing on the two dozen or so builds. There is a somewhat working Tetris port, the input routines, game logic, and text output is working, but I've got some work to do on the "graphics" glue. There are some useful characters in the font which allow turning the 32x16 text display into a 64x32 graphics display which will come in handy for rendering the playfield.
Interesting things to explore in the near future:
- Figure out how to get the 80C88 in charge of the disk drive to do useful things... Like maybe loading and saving data files for us?
- Asteroids and other games ported from Texas Instruments calculators... (Tetris port came from here)
- Figure out what all these extra CPUs/MCUs are doing (There's 5 processors with 4 different instruction sets!)
- Video hacking! - Is there a way to change the CRTC parameters to output a different resolution like the 4957? Can we lock onto the video refresh and race the beam for doubling or quadrupling the vertical resolution?
- GPIO/USART expansion - Making our own PODs
- CP/M with HP 120 (9122) compatible disks...