Hy, I would like to control dot matrix display on BMW e39 business radio (Becker BE 3350), that uses 1 PCF8579 and 2 PCF8578 row /column drivers.
INTRODUCTION TO MY PROJECT
I want to add usb playback to the radio. I sorted out ibus interface with arduino, but I cannot send messages to lcd via ibus.
PROGRESS SO FAR
On the frontplate I had traced i2c wires, i2c scanner finds adress of PCF8578 (0x3c), PCF8579s are controlled with PCF8578.
Now that I know I have connection and adress, I would need a code / library for it. There is nothing online.
I would need to make my own code, I have the datasheet that explains the i2c part, but I don't understand it.
PCF8578 is a row driver and PCF8579s are column drivers. I still need for count rows and columns of display.
I will study it and try to make it work, I would be grateful for any explanation on how to do it.
So if you know anything about it please let me know.
When finished I will post whole project, wiring, schematics, library and code, etc... so others can make this mod within few hours.