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HP 71B Diagnostic ROM
04-13-2014, 01:24 AM
Post: #9
RE: HP 71B Diagnostic ROM
(12-30-2013 06:53 PM)Dave Frederickson Wrote:  Speaking of this newly acquired 71, it's the newer version without the flex connecting the PCBs, with date code 2707, yet the ROM version is 1BBBB. There's a 2CDCC on EBay with a date code of 2515. Why does this newer 71 have older firmware?
I'm sure the HP-71B with datecode 2515 either has transplanted innards from a later unit, or at least the back side has been replaced.

I have seen HP-71B units from 1987 with ROM 1BBBB, and the update to ROM 2CCCC happened in 1987, and shortly after the first upgrade the ROM 2CDCC was released.

-- Ray
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Messages In This Thread
HP 71B Diagnostic ROM - Dave Frederickson - 12-19-2013, 08:06 PM
RE: HP 71B Diagnostic ROM - Reinhard Hawel - 12-27-2013, 04:41 PM
RE: HP 71B Diagnostic ROM - Reinhard Hawel - 12-30-2013, 11:00 AM
RE: HP 71B Diagnostic ROM - Reinhard Hawel - 12-30-2013, 10:48 AM
RE: HP 71B Diagnostic ROM - Raymond Del Tondo - 04-13-2014 01:24 AM
RE: HP 71B Diagnostic ROM - Joe Horn - 04-13-2014, 03:58 AM
RE: HP 71B Diagnostic ROM - Joe Horn - 04-14-2014, 11:06 PM



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