I'm looking for a Fanuc perforated paper Tape Reader schematic. I'm in he process to build an BTR circuit, but would like to well understand the tape reader PCB circuitry before. I have started drawing by hand; removed almost all the IC's to have good tracks view. There is some 6 pin resistor network chips that I didn't find, and looks is two separated resistor circuits as the ohm reading are kind odd.
The goal is to build a Beyond Tape Reader interface for a Fanuc 6M controller, using an Atmega uC.
The tape reader is : A13B-0070-B001
The tape reader PCB: A20B-0007-0750/07B
The resistor network below is 6 pin. Pins #5 & #6 looks to be a single resistor 17k, but pins #1 to #4 could be some sort of bridge resistor circuit as the ohm readings are not normal.
Hope someone have the tape reader schematic, to compare. I will upload mine when I finish to trace all the circuits.
Im mostly interested on the 50 pin connector signaling.