[Milsurplus] IBM PC

[J. Forster]

Ray Fantini wrote:

. The IBM had DOS, ok so it's a Microsoft reverse engineered version of CPM, but
once again everyone else used it, well except for Mac people.

DOS was around YEARS before. There was certainly a stripped down version of DOS,
loaded from paper tape onto a head per track hard disk with a capacity of 64K 16
bit words and up in about 1969. It was the DG 4019A and used an Alpha Data
drive. They were available in sizes up to at least 512 KW. Small, but fast. No
head seek time, just the latency. That DOS would run in something like 8 KW.

There were two versions, RTOS (Real Time Operating System) and RDOS (Real Time
Disk Operating System). I first came across RDOS with the Diablo 31s which were
pizza oven like 2,5 M hard drives (IBM 2315s).

IMO, S-100 and CPM were significantly later.

-John