Software
The Big Board was designed primarily to run the CP/M operating system, version 2.2. It came with a monitor program in ROM called PFM-80 which was the "software front panel" of the system. The source code listing of PFM was a feature of the first and second issues of Micro Cornucopia. PFM featured many well-documented routines that could be employed in user code.
The board featured 3 spare 2K ROM sockets that allowed for the addition of additional firmware. Popular additions were Tiny BASIC, FORTH, and enhanced versions of PFM.
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