iBook G4 Clamshell Keyboard pinout?

[sircastor]

This is a longshot in general, but I've seen plenty of folks hacking away at their 1st gen iBooks. Does anybody know what the pinout is for the 40-pin connector that goes from the keyboard to the iBook. The pitch for the pins is ~1mm (I think, these are hand-measurements) I know virtually nothing about how keyboards multiplex values, so I'm hoping someone has done some of the footwork already 😁

Any help is welcome.

 

[sircastor]

As I was poking around, I found someone had already gone through the struggle
Many thanks to @rorydaredking for writing down the exploration process

It's not a pinout specifically - but information and links to data for reading from the keyboard matrix.
If you're also looking: https://forums.macrumors.com/threads/modern-ibook-clamshell-project.2343696/

 

[sircastor]

Okay, after quite a bit of work and a fair bit of help, I have mapped out the G3 iBook Clamshell keyboard pinout. I don't want anyone to suffer through doing this when we live in a world where data is shared so freely and broadly. I'm posting here for redundancy (though my site's version isn't up yet)

This image shows how the pins on the mating connector map to the rows and columns matrix.

• The red keys are rows
• The black keys are columns
• The blue keys connect a pin to ground
• The two magenta numbers are pins to the power and Caps Lock LEDs.

Here is a schematic of the mating connector that would go on the logic board (or an adapter) and the connector on the iBook G3 logicboard.

It's worth noting that pins 2, 4, and 6 clearly are routed to something on the logic board, but it's not immediately obvious what - and all features of the keyboard are accounted for.

The keyboard connector is 2x20 1.27mm pitch. Arguably, any connector you found that matches that should work but other folks who have pursued this end up getting this connector from proto advantage.

If you're trying to figure out a microcontroller to work with it, I've had excellent success with a Raspberry Pi Pico (an RP2040) running KMK keyboard firmware. This setup requires more pins than are available if you want all keys plus the LEDs - I'm still working on a shift register setup to free up some pins for other things.