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

Recover Mac Files Old SCSI

Summary

This blog demonstrates how a Linux PC and SCSI PCI card can be used to retrieve the files from the SCSI hard disk of a twenty year old Power Mac.

Power Mac
The Power Mac 6100/66 was possibly the third Mac that I had the pleasure of owning back in the day. The 'pizza box' as it was affectionately known, had 24MB of RAM, 16bit colour, a proprietary Ethernet interface and no USB connection or CD burner.

Power Mac 6100/66

Somehow twenty years later, my belief was that the machine had long been retired from use, the old Mac turns out to have a family members five year old files stored on the hard drive. To make life a bit more interesting the floppy drive, similar to most of the plastic in the old Mac, has degraded to the point of failure. 

Inside a Power Mac 6100/66

Fortunately the Mac still booted verifying that the internal SCSI drive was mountable. After removing the cover from the Power Mac the non-Apple drive was easily visible at the bottom left hand corner of the above image.

SCSI Controller
After performing price comparisons between a second hand Apple Network adaptor and a replacement floppy drive, it turned out that there was alternative solution. One of the online stores was selling off some AdvanSys ABP 3922 SCSI Controllers.

AdvanSys PCI SCSI Controller

CNET had a basic specification for the ABP 3922 which indicated this card was suitable for PC or Mac. 

AdvanSys PCI SCSI Controller Rear

The online store price for the card ended up significantly cheaper than purchasing an Apple Network adaptor and also less than a suitable replacement Panasonic 1.44Mb Superdrive.

AdvanSys ABP 3922 SCSI Controller

Linux
Fitting the SCSI Controller into an existing Linux tower running Mint, a quick check of the PCI bus using LSPCI this indicated that the card has been detected.

PCI SCSI Card Identification

With the card detected in Linux the Mac SCSI drive was hot plugged to the 50 way IDC connection and powered.

Mac Formatted SCSI Drive Connection

Under Linux Mint the drive auto mounted and could be located in the usual location under the Computer icon.

Linux Mint Computer Icon

As part of basic troubleshooting, a drive that has not auto mounted could be checked in the Linux 'Disks' tool.

Linux Mint Disks with Mac Drive

Old Mac drives were formatted in HFS or HFS+ both of which Linux will commonly mount without any issues.

File Retrieval

With the SCSI drive mounted the required files could be accessed and copied off the SCSI drive. It should be noted that some specific files relating to preference files for games were not able to be copied.

Summary
Using an older model SCSI PCI card, which suits an existing motherboard together with Linux, was an inexpensive solution to retrieve files from an old Mac drive. The same methodology may even work for some of the single board computers with the addition of a USB to PCI bridge or for other platforms a suitable USB interface such as the discontinued but still available Adaptec USBXchange adaptor.