Re: Mystery Ancient HP Memory Modules Message #4 Posted by Vassilis Prevelakis on 8 Mar 2004, 10:03 a.m., in response to message #1 by Alex
Looks like one of the 14 OS ROMs for the 9825A.
Unlike later models (B and T), the A model had a drawer
on the left side. This drawer contained 14 plug-in ROMS that had the OS code.
The ROMs look a like the HP-85 ROMs, plastic packges with
holes on the underside. Spikes on the daughterboard enter the holes to make contact with the ROM PCB.
Unlike the 85 ROMs, the HP 9825 OS ROMs have holes all around the edges.
I don't have a picture of the 9825 ROMS, but here is a picture of the 85 ROM drawer:
**vp
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