Questions tagged [cp-m]
For questions related to the CP/M operating system by Gary Kildall.
78 questions
3votes
0answers
149views
CF Card Issues - DIY Z80 COMPUTER from scratch - CP/M frozen after boot
has anyone here ever had a similar problem? I'm basically trying to use my CF card interface board that used to work with another memory card, which unfortunately got damaged (my fault). Now I only ...
12votes
2answers
427views
Are there any MP/M multiplayer games?
MP/M systems were capable of having multiple simultaneous users on terminals sharing files. Are there any known examples of games that leveraged this to create multi-player games where players would ...
- 797
3votes
2answers
637views
How can I use GSX in Turbo Pascal for CP/M-80?
Several versions of CP/M Plus came with a device-independent graphics library called GSX. It would be fairly easy to call this from Turbo Pascal: the CP/M-80 version of TP3 includes a function Bdos. I ...
- 3,925
5votes
1answer
632views
Were any full-screen programs sold for Commodore 64 CP/M?
The various shortcomings of the Commodore 64 CP/M cartridge are fairly well-known (40-column screen, limited to GCR-format disks, restricted TPA size, slow disk access). One that doesn't seem to be ...
- 9,015
2votes
1answer
397views
What CP/M systems with where BOOT ≠ $0000 do or do not allow a BDOS entry at $0005 rather than BOOT+$0005?
While not standard, there were several CP/M systems (such as ones for TRS-80 Model I and Heath H89) where BOOT was not at $0000. As mentioned in that question, the Digital Research manuals explain ...
- 28.5k
10votes
1answer
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How did one run CP/M on Spectrum computers before the Spectrum +2A/+3?
Wikipedia says, "[The Spectrum +3] was the only Spectrum model capable of running the CP/M operating system without additional hardware." (But the +2A used the same motherboard, and thus ...
- 28.5k
3votes
0answers
294views
Were CP/M systems based at $4200 a "standard"?
According to the CP/M 2 manual, the standard locations for BOOT (where you jump to do a warm start) and TBASE (the start of the transient program area or TPA) are $0000 and $0100, respectively. This ...
- 28.5k
17votes
5answers
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Unix tools for manipulating Commodore CP/M disk images
I'm looking for some (command-line) tools that can transfer host files on a Unix or Linux machine to and from Commodore .D64, .D71 and similar image files in CP/M format. The particular use case I ...
- 28.5k
10votes
3answers
1kviews
How was MP/M’s time sharing implemented?
MP/M, the multi-user sibling of Digital Research ubiquitous CP/M, implemented time-sharing in a way that appears to be very efficient. Processes don’t appear to see each other’s memory and performance ...
- 797
19votes
1answer
561views
Was CP/M 2.1 released, and if so can it still be found?
When I got into CP/M computing it was the CP/M 3 era, so I picked up my understanding of earlier releases second-hand rather than experiencing them in person. My understanding of the history of 2.x ...
- 9,015
12votes
1answer
445views
What's the earliest source for the legend of Gary Kildall's airplane snub?
A commonly repeated (and commonly debunked) legend describes how Gary Kildall blew his chance at writing the operating system for the IBM PC. Examples include the following: …legend has it that ...
- 7,771
16votes
4answers
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How do I properly exit a program and return to the CCP in CP/M?
Once my CP/M program has finished doing whatever it's supposed to do, or the user chooses some sort of "quit" option, how do I return the user back to the CCP? Can I just do a ret? Or do I ...
- 28.5k
2votes
3answers
722views
Z80 to 68000 translator for CP/M
CP/M was mostly portable across systems but most of them were z80 based. It was ported to 8086, 68000 and maybe more but without binary compatibility. No z80 systems that wanted CP/M compatibility ...
- 1,389
13votes
4answers
3kviews
In CP/M, how did a program know when to load a particular overlay?
Here is what I understand so far: A program that was too large to put into main memory was broken into several overlay regions. Once you needed data from outside of the currently loaded region, ...
- 3,727
21votes
1answer
1kviews
Are any CP/M systems still in commercial use today?
I understand that there is a great deal of mainframe-era enterprise software that is still in active use, if not on the original hardware then in emulated environments. Its users keep it running ...
- 7,771
