HP-65 1333A18516 - [SOLVED] request for advice

[teenix]

Pin 8 of the cathode driver is the Reset Pin (1820-1226)
Pin 9 is the STEP IN pin from the anode driver.

Pin 6 of the Anode driver is the STEP OUT pin to cathode driver. (1820-1029)

Both pulses are on page 12 of the Classic Notes.

I'd make sure these pulses are there, and if not check the traces back to the board.

The RCD pin from the CPU board is the left-most interconnect pin to the keyboard.

You might like to check the ABCDE lines to the anode driver as well, The signals image on page 10 of the Classic notes.

Other end of interconnector, right side pins counting left, 1 2 3 6 and 7. Pins 1 2 3 4 and 5 on anode driver.

cheers

Tony