Apple M2980 Membrane Matrix Pinouts

Summary

This blog details the membrane connector pinouts for the Apple M2980 keyboard and the associated key matrix.

Apple M2980 Keyboard

The rear nameplate of the keyboard had the details as pictured below.

M2980 Nameplate

Keyboard Hardware
The M2890 model keyboard lends itself to custom project projects because this model had the keyboard row and column keys available on two membrane connectors.

M2980 Keyboard Internals

Shown above is an image of the keyboard with the back off. For those paying attention that is 'liquid' damage toward the left hand corner of the image above.

A close-up of the circuit board 'PCB' which encodes the key presses into the Apple ADB format is pictured below.

M2980 PCB

For the custom project the original PCB was removed and the keys matrix for the two membrane connections (row and column) decoded manually. 

M2980 P1 and P2 Connector Pin Numbering

Several directly soldered PCB connections to the back of the PCB, continuity measurements using a multimeter and a multitude of key presses later, the matrix table shown below 'represents' the state of the keyboard used for testing.

Keyboard Matrix Connections

M2980 Membrane Matrix Connections

The information listed in this blog should be used for reference only and remains the intellectual property of Apple Inc and its subsidiaries. 

As noted in this blog, the original keyboard did have previous 'liquid' damage and not all keys may have been mapped. 

For the above shown table the Column connections (C0 through C8) refer to the P1 connector (Pins 1 thru 9). Columns start at 0 and the connector pin numbering starts at 1. Similarly the Row connections refer to the P2 connector - same numbering concept.

It should be noted that even after twenty years since its manufacture, this 'economical' model of the Apple keyboard can still find a purpose for the home hobbyist. 

Mouse Hardware
As a side note, the Apple ADB mouse associated with the keyboard was also being literally torn apart to access the microcontroller (possibly an early PIC) when I noted something curious. 

Whether required as part of the physical design of the mouse, or a cheeky play on the die design for the ABS plastic by the Mechanical Engineer(s) in the project, it made me consider where Apple was, where it is now and when it all changed. No doubt face for thought!!

Apple ADB Mouse Torn Down