The CBM II line

CBM II: By 1982 the the five year old PET was starting too look tired and Commodore decided to give the whole series a facelift and offer many improvements.

Three new computers were announced at theSummer and Winter CES of that year - the first was the P500 (later renamed to the P128) with a MOS 6509, 40 column display, two joystick ports 128KB RAM expandle to twice that, 16 colour graphics and the ability to add a Z80 coprocessor board (never made available however).

The second machine was the B700, later enhanced and expanded and renamed to the BX256 this was a business model featuring dual processors - the 8 bit 6509 and the 8/16 bit Intel 8088 promising MS DOS compatibility. It was expandable to a huge 704KB or RAM and included integrated disk drive, 80 column colour display and all the usual Commodore ports of the time. It was claimed it was able to run CP/M-86 as well.

The third machine introduced was the B128 which was similar to the B700 but did not include the 8088 (optionally available).

These machines all received various names depending on where they were sold - the entire list is B128, P500, B500, B256, B700, CBM 128-80, CBM 256-80, B128-80, B256-80, CBMX, 500, 600, 610, 620, 700, 710, 720 and 730. Confusing to say the least especially considering that so few had been produced. Around 3,000 of these machines were released and there are differences amongst them all with various engineering cjhanges being made during production. Peripherals had been developed but users could also take advantage of all the PET peripherals as these were also compatible.

There is an urban legend that the case design was done by Porsche; however that is not true - the cases were designed by a Commodore employee (Ira Velinsky) who won an award for them in 1983. When the series was canned Commodore in typical fashion used existing stock to house the new 8000 line.

Production was halted in 1984 but it wasn't quite the end for these machines. In that year Commodore engaged Protecto to liquidate the remaining stock and at the same time a dedicated user group was banding together to support the machine. In 1985 the group (CBUG) released their first newsletter and shortly afterwards became an international organisation. CBUG managed to get most of the 8088 boards from Commodore and went on to develop software and update some of the system software. CBUG was to fold in 1989.