Re: Cp/m 86

Industry standard 286's (e.g. PC-AT clones) did have a CMOS clock and memory that maintained the time, data and system parameters (including the hard and floppy disk types), and it was battery backed up. In those days, the battery was usually not "on" the motherboard, but was an offboard battery that connected to the motherboard with a polarized 4-pin header connector. The bios setup program (a clear ancestor of what we see today) did not exist in the BIOS but was a separate program supplied on floppy diskette. If you lost the floppy, you could be SOL, although most of them were interchangeable between motherboards.


Bill H wrote: 
This 286 doesn't have a bios that is accessable via any key press (ie
F1, CTRL DEL) etc and no battery on the motherboard. I saw mentioned
that there is a program to access these bios - but don't know how they
would save anything without any battery on the motherboard.

The FD controller contains all the Serial, Parralel and Game ports and
has it's own cpu on it. The HD card also has its own Z80 cpu running
it.

Maybe I have a wierd mystery machine here. It says IBM Personal
Computer on the front case, but there is no mention of IBM or any other
company) anywhere on the motherboard.

.

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