HP-65 more on the card reader

[teenix]

(02-15-2019 09:23 AM)albertofenini Wrote:  Hi Tony,
exactly the same type that were in place, we got them from a stripped logic board from another HP65 which
had a broken CPU.
They works, since the unit operates well, and read cards.
We also re-soldered the WA and WB pins of the CPU just in case, but nothing.
Take care and thanks for help

Thanks Alberto,

If I am correct in saying the card will write unless it is assembled into the case and then it fails...

Have you tried isolating the WB pin from the main cpu board to the card reader board leaving all other pins connected normally. Probably difficult to do without bending the WB connector pin and risking damaging it.

That way it might prove whether the fault is on the cpu board or reader board.
You should still be able to see the cpu WB signal even though it doesn't get to the sense chip and see if it is good or bad.

cheers

Tony