CP/M operating systemWriting another page about CP/M is probably pointless, as there is a lot of great material around the web, like on wikipedia.
Time ago, when I got PIC32MX795F512H
into my hands, I was really impressed with its memory capabilites.
128kB of RAM is quite a lot for such as cheap MCU, but I didn't know
what to do with such as amount of memory. Approximately at the same
time I became interested in old operating systems and found a lot of
old software, written by clever programmers in unbloated way (word
processor in 19kB, for example), which had to run on hardware, very
limited from perspective of nowadays computers. That PIC32 has also a
lot of horsepower, at least on order of magnitude higher than Z80 those
days and after seeing Z80 emulator, Z80pack
from Udo Munk, which could run on 386 class of computers (in some
aspects very rough equivalent of PIC32), I decided to port core of
his emulator on PIC32, write my own peripherals and disks emulation,
what would give me virtual Z80 machine. For this machine I wrote
my CP/M BIOS and let CP/M run above this BIOS.
As usual, no firmware or schematics for now.
You can check my picasa photo albums - first try - with LCD 4x40 and second one on "real" PCB and GLCD 240x128 pixels with LCD driver, emulating VT100 compatible terminal with resolution 60x16 characters.
it runs Turbo Pascal, WordStar (or ZDE, even smaller word
processor),there is a lot of other compilers and interpreters (like
HiSoft C compiler, Microsoft MBASIC, Forth, LISP, Algol, Fortran),
compression programs (ARC), games (Zork) and even tools for cross
development (8048 assembler) or emulators of another CPUs (what about
6502 emulator running on emualted Z80 running on PIC32?).
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