CP/M-86

From Wikipedia, the free encyclopedia

CP/M-86 was a version of the CP/M operating system that Digital Research made for the Intel 8086 and Intel 8088. The commands are those of CP/M-80. It was later reworked to become MS-DOS compatible and renamed to DR-DOS and is discussed at more length in that article.

1 CP/M-86 and the IBM PC
2 Versions
3 Notes
4 External links
5 See also

[edit] CP/M-86 and the IBM PC

When IBM contacted other companies to obtain components for the IBM PC, the as-yet unreleased CP/M-86 was its first choice for an operating system because CP/M had the most applications at the time. Negotiations between Digital Research and IBM quickly deteriorated over IBM's non-disclosure agreement and its insistence on a one-time fee rather than DRI's usual royalty licensing plan.^[1] After discussions with Microsoft, IBM decided to use QDOS, a CP/M-like operating system that a Seattle area computer company had made for its own hardware. Microsoft adapted QDOS for the PC hardware and IBM shipped it as PC-DOS.

After learning about the deal, Digital Research founder Gary Kildall threatened to sue IBM for infringing DRI's intellectual property, and IBM agreed to offer CP/M-86 on the PC to settle the claim. CP/M-86 was released a few months after the PC and was one of three operating systems a customer could buy from IBM. At $240 per copy it sold poorly compared to the $40 PC-DOS. Kildall would later accuse IBM of setting the prices to marginalize him, but the accounts of Microsoft, IBM, and other DRI executives indicate that Kildall had demanded a substantial royalty for CP/M-86 while Microsoft had accepted a fixed sum. Customers rapidly adopted the PC platform with PC-DOS as the new industry standard, and opportunities for DRI to license CP/M-86 to other customers dwindled.

[edit] Versions

A given version of CP/M-86 will have two version numbers. One applies to the whole system and is usually displayed at startup; the other applies to the BDOS kernel. Versions known to exist include:

CP/M-86 for the IBM Personal Computer Version 1.0 (BDOS 2.2) - January 1982 - Initial release for the IBM PC.
CP/M-86 for the IBM Personal Computer Version 1.1 (BDOS 2.2) - March 1983 - Hard drive support was added.
Personal CP/M-86 Version 1.0 (BDOS 3.1) - November 1983 - Released for the Siemens PG685. Based on the multitasking Concurrent CP/M kernel, it could run up to four tasks at once.
Personal CP/M-86 Version 3.1 (BDOS 3.3) - January 1985 - A version for the Apricot F-Series computers. This version gained the ability to use MS-DOS formatted disks.
Personal CP/M-86 Version 2.0 (BDOS 4.1) - 1986 or later - Released for the Siemens PC16-20. This is the same BDOS used in DOS Plus.
Personal CP/M-86 Version 2.11 (BDOS 4.1) - 1986 or later - Released for the Siemens PG685.

It is believed that the various Personal CP/M-86 versions were based on an unreleased product known as CP/M-86 Plus; all known Personal CP/M-86 versions contain this string.