HP 65 Card reader task

[teenix]

pin 14 is a GND connection

with the CPU board in and powered on in RUN mode, maybe with jumper leads to the battery terminals, -ve towards the top, measure the voltage on pin 17 of the sense chip. It should be around 6V.

If you push a card in to the drive wheel, this voltage should drop to zero.

If it does, make sure pins 16 and 18 have around 3.8V.

GND pin on the sense chip is pin 7.

pin 11 should be GND for a card read

pin 1 to the motor +ve should be around 2.5V

cheers

Tony