Commodore CBM-II

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Image:Cbm710 ta.jpg The Commodore CBM-II series was a short-lived range of 8-bit personal computers from Commodore Business Machines (CBM), intended as a follow-on to the Commodore PET series, released in 1982.

1 Technical description
2 History
3 CBM-II trivia
4 Notes
5 External links

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Technical description

In the United States and Canada, the CBM-II had two incarnations, the P series (P = personal, i.e, home use) and the B series (B = business use). The B series was released in Europe as the 600/700 series (no "B" in front of the model number). Both P and B series used a MOS Technology 6509 CPU, an enhanced version of the venerable 6502, that was capable of addressing up to 1 megabyte of RAM via bank switching (however, no CBM-II model came with more than 256 kilobytes of RAM, 1/4 megabyte). The sound chip was the 6581 SID, the same one that was used in the popular Commodore 64 (C64).

The P series also used the VIC-II color video chip from the C64. The B series used a 6545 CRTC video chip in place of the VIC-II to give an 80-column "green screen" monochrome output more suitable for word processing and other business use than the VIC-II's 40-column display. An optional Intel 8088-based coprocessor board allowed the CBM series to run CP/M-86 and MS-DOS 1.25; however, the computers were not IBM PC compatible and very little, if any, software taking advantage of this capability ever appeared. The CBM-II's built-in operating system running on its native MOS 6509 processor was a version of Commodore's KERNAL in combo with CBM BASIC version 4.0.

Like the PET series, the CBM-II featured an IEEE-488 parallel bus for use by disk drives and printers and was completely compatible with the drives and printers for the PET line. Additionally, the CBM-II had an industry-standard RS-232 serial interface.

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History

Due to the popularity of the C64, the P series was cancelled in the United States before it could be officially released; however, a few dealers who received preproduction units sold them. As these computers had not received approval from the Federal Communications Commission, this caused legal problems for Commodore. The units were recalled and destroyed, but a very small number exist today, in private collections. At least one model, the P500, was commercially released in Europe but only sold in small numbers.

The most common of the B series was the B128Template:Ref label (called the CBM 610 in Europe), which had 128 kilobytes of RAM. The B128 did not sell well, and ultimately Commodore's inventory was liquidated by Protecto Enterprises, a large Commodore mail order dealer based in Chicago, Illinois. The Protecto ads for the B128 bundle, including a dual disk drive, monitor and printer, appeared in various computer magazines for several years.

After discontinuing the CBM-II range, Commodore handed its documentation, schematics, and all other information over to the Chicago B128 Users Group, who developed a library of software for the computers. Its library, however, paled in comparison to the large software libraries enjoyed by the C64 and Commodore VIC-20.

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CBM-II trivia

A B128 made a brief appearance as a prop in the 1985 movie The Jewel of the Nile, starring Michael Douglas and Kathleen Turner.

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Notes

Template:Note Template:Note label Neither the CBM128-80 nor the B128 are to be confused with the very different and reasonably successful Commodore 128 (aka CBM 128 and C128), Commodore's final 8-bit home/personal computer, released in 1985.

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