HP 9845 -- Language Processor Defect (?)



#3

I've been given a HP 9845B (the first computer I ever touched, 23 years ago). When powered on, it hangs up with the "MEMORY TEST IN PROGRESS" message (except that it responds properly to CONTROL-STOP). All supply voltages seem to be reasonable, both on the test points and on the left-hand set of boards.

I think I can recall dimly that the I/O Processor (which also controls the CRT) is responsible of performing the power-on tests, prior to resetting (and passing the control to) the Language Processor. Therefore, it appears the Language Processor may be bad, but I have no idea how to identify the defect closer. Obviously I don't wish to make more harm than anything else.

I would be grateful for any advice.

Petr


#4

I have ingood fit HP9845B and moor options.
Olda


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