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Sunday, April 11, 2021

CONTINUITY: HP 9825 Repair Part 2: Is Our Rare 16-Bit Processor Fried?

In Part 1, the catastrophic failure of the power supply was analysed and repaired, but that didn't fix the computer, indicating damage elsewhere as a result. Now the investigation digs deeper into the circuitry, checking the clock generation and memory access signals from the processor. There's excellent background about Hewlett-Packard's pioneering 16-bit processor built from multiple chips on a hybrid substrate.

Posted at April 11, 2021 13:59