Whatever Happened to CP/M? (Part 1/2) #cp7mber

Part one of this two-part series dives into the early days of personal computing, from the birth of the CP/M operating system in 1974 to the rise of the IBM PC in the 1980s. Follow the journey of Gary Kildall, the visionary founder of Digital Research, whose pioneering software set the stage for modern computing. Explore the critical moments and decisions that shaped the industry, including the fateful encounter with IBM that changed the course of tech history; from triumphs to missed opportunities.

00:00 Intro
00:38 CP/M: The de-facto 70's standard operating system
01:50 The origins of CP/M: 1974 at Intel
04:45 DRI & The IBM PC: A missed opportunity?
07:15 DRI's Downfall, and the end of CP/M
13:32 Next on TPC: Becoming DR DOS - Whatever happened to CP/M, Part 2

Links:

Historic Systems:

Altair 8800:
Altair-Duino Replica:

Hardware Abstraction:

Emulation:

CP/M Versions:

IBM, Intel, Microsoft, SCP backgrounds:

Novell's side of the history:

Historic Backgrounds:

Copyright @ 2024 THE PHINTAGE COLLECTOR, Gianpaolo Del Matto. All rights reserved.

Theme Music composed by Abdallah El-Ghannam.

Additional music featured by rootkitty

[toddbu-WKL]

Not only did I have a CP/M machine back in the day (which I truly loved), but I also owned an MP/M machine for a while too. For those of you unfamiliar with MP/M, it was a variant of CP/M that allowed for memory bank switching. When multiple programs were run, they were each loaded into (as I recall) a 16KB bank of memory that could be switched on and off. When switched on, the memory was overlaid with the other switched banks, meaning that only one bank at a time could be enabled. When it was time to give some CPU cycles to a program, the processor would save the context of the currently running application, turn off its memory bank, restore the saved context from the next app to schedule, switch on its memory bank, and start executing. It was a very cool way of multitasking, even though it required specialized hardware and was not memory efficient (memory banks could not be shared). Anymore these days MP/M looks like a dinosaur, but at the time it was pretty cutting edge.

[hmichaelkraut]

Enjoying the episodic nature. Appreciate your videos and many thanks for the time and effort

[jasejj]

CP/M actually lasted quite a long time. The Amstrad PCW, a Z80-based, low-cost business machine used CP/M, and was extremely successful in the UK and elsewhere in the 1980s and '90s, outselling PCs for a while and eventually became the best selling British computer ever. Amstrad's smaller home micros, the CPC range (which was also commonly used in small businesses) and the Sinclair Spectrum +3 also could run CP/M.

[Michael.Werker]

The problem with the lots of MFM disk formats forced Commodore to add the WD1770/71 floppy controller into the 1570 and 1571 drives to be useable with CP/M on the C128.

The C128DCR combined the C128 and the 1571 into one PCB, so it is one of the few boards with three different processors: 6502, 8502 and Z80. But Commodore also combined a 6526 and the WD1771 into the disk controller 5710. It required a new CBM DOS 3.1 which wasn't as compatible as DOS 3.0 of the original 1571. But I don't know how it affected CP/M compatibility.

[erie]

Ran Windows for Workgroups over DR DOS 6. It was more stable than running Windows over any MS-DOS version.

[chadvanderlinden]

D'er Doss? I think you'll find it's pronounced "Doctor Doss".
Anyway, while I don't hear this said today, back in the 70's and 80's it was widely known that CP/M was originally just written so a disk drive manufacturer could demo their product. After popular demand, it got expanded. I had CP/M on my TRS-80 COCO 2 and unmodified TRS-80 Model I (with expander). LDOS was better.

[erikp]

Very nice! However, where did you get the timeline of cp/m and dr dos (at about 11:04)? I cant find it when I google it.