« Reply #3 on: August 19, 2022, 07:25:17 am »
Here are the Revox B261 uP control block diagram, the uP controller schematic (which has a SAA1061-3 port expander) and the keyboard schematic which has a SAA1061-2 chip and a CD4532 priority encoder chip. I'm assuming that the -3 and -2 after the chip part number referes to the address that can be hard wired using pins 4 and/or 7 by connecting to VDD or ground as required. I am not sure how SAA1061 is addressed in the serial data stream or how the port direction is set? Can anyone help? Thanks.
PS. SAA1061 datasheet is in the first post to this topic. Thanks.
« Last Edit: August 19, 2022, 11:29:21 am by djsb »
Logged
David
Hertfordshire, UK
University Electronics Technician, London, PIC16/18, CCS PCM C, Arduino UNO, NANO,ESP32, KiCad V8+, Altium Designer 21.4.1, Alibre Design Expert 28 & FreeCAD beginner. LPKF S103,S62 PCB router Operator, Electronics instructor. Credited KiCad French to English translator