Commodore 128

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Commodore 128
Commodore 128.jpg
A Commodore 128
Manufacturer: Commodore Business Machines
Year Introduced: January 1985
Form Factor: Microcomputer
Clock Speed: 2 MHz
Memory Size: 128 KB in two 64KB banks
CPU: MOS 8502, Zilog Z80
Operating System: BASIC, CP/M

The Commodore 128 was featured as a 3 in 1 computer. The CPU could run at 2MHz, and address 128KB of RAM. This was largely taken from the 'B' line of computers that Commodore sold in Europe. The Commodore 128 could also emulate in hardware a Commodore 64. As such it could use all of the peripherals from the Commodore 64. Lastly the 128 had a Zilog z80 co-processor and could run CP/M. Along with the 1571 floppy drive, it could even share data with a variety of other CP/M machines.

For the most part, people used the Commodore 128's as Commodore 64's, as few vendors felt the need to write for the 128, when the 64 emulation was so good, they could keep selling to all segments. However there were special versions of Geos, and some Infocom games that took advantage of the higher resolutions & main memory that were available to the 128.

The machine would run at 2MHz in C128 8502 mode, and 4MHz in Z80 mode, although effectively 2MHz there as well due to wait states to give video access to system bus. In C64 compatibility mode the 8502 dropped down to 1MHz.


The Commodore 128 was replaced by the Amiga line of computers.