RunCPM for Picomputer - Z80 CP/M emulator for Bobricius' Picomputer (unofficial release)

RunCPM was written by Marcelo Dantas, then ported to RaspberryPi Pico by GUIDO LEHWALDER.
This is a port of the latter to Bobricius' Picomputer, for which I had to add the ST77XX Adafruit screen driver and my own keyboard and sound drivers.

The original work can be found at these locations :

(c) Marcelo Dantas https://github.com/MockbaTheBorg/RunCPM
(c) GUIDO LEHWALDER https://github.com/guidol70/RunCPM_RPi_Pico/tree/main/v6_8

Some details

• The screen is 53x30 characters. As it is pretty slow and doesn't support effectively scrolling, I use the same trick that is used by PicoMite for such screens : erase the screen and go to the top when you reach the bottom.
• The last line is used to display the status of the fake-scrolling operations
• A minimal subset of VT100 codes is supported, just enough so TurboPascal 3.0 barely works, that is EEOL, CURPOS and colors (Esc[<n>m Esc[38;5;<n>m and Esc[48;5;<n>m)
• You will find my TurboPascal parameter file in the support_files directory with a 'PICOMPUTER' choice in the screen section, if that helps.
• The CPU is overclocked, running at 250Mhz, giving you about 7 times the speed of a 4Mhz Z80.

Keyboard

• SHIFT-DOWN : select LowerCase (then the shift key acts more like an ALT one, to select symbols)
• SHIFT-UP : select UpperCase (then the shift key acts more like an ALT one, to select symbols)
• SHIFT-RIGHT : select Symbols (then the shift key acts more like an CTRL one, to select control characters)

Installation

Set your pico in boot mode, then copy the uf2 file (found in build/rp2040.rp2040.rpipico/) to the device.
Note that if the firmware is already loaded, you can hold the "Q" button during reset to enter the boot mode.
You need to prepare a SD card with CP/M on it, found here : https://github.com/guidol70/RunCPM_RPi_Pico/tree/main/SDCard_content.zip I suggest you add on that SD card some CP/M content you can find here : https://obsolescence.wixsite.com/obsolescence/multicomp-fpga-cpm-demo-disk (choice: Download Tool Set, not the Disk Image)

Instruction for creating the SD card may be found here : https://github.com/guidol70/RunCPM_RPi_Pico/tree/main