Apple ADB Keyboard recognized but no keys work?

[Fizzbinn]

So weird problem, I have an Apple ADB Keyboard (M0116) that has no problem starting a Quadra 700, the Apple Desktop Bus Mouse connected through it works fine, yet none of the keys are recognized... Key Caps shows it recognizes a standard ADB keyboard (as does TattleTech) so it's working to some level. Anyone have any ideas?

 

[Fizzbinn]

More data points, swapping in an Apple ADB Keyboard II works just fine for the Q700 and test the suspect Apple ADB Keyboard with my SE/30 also works fine. Back to the Q700, same issue, bizarre...

 

[Arbee]

The keyboard works 100% on the SE/30, but on the Q700 only the power key works? That's really strange.

 

[Fizzbinn]

Agreed.

Although the power key only works for the initial start-up kick-off, once booted when pressed it is not recognized by Key Caps, just like all the other keys. Yet TattleTech on the Q700 seeing the Standard Keyboard in its list of ADB devices and the mouse connected through it works just fine. The only thing coming to mind is some kind of power issue? I need to try the problematic keyboard on some more Macs for more data points I suppose...

 

[saybur]

It might be a power problem but it apparently works well enough to be detected and go through the whole ADB address dance routine, AFAIK it shouldn't show up in the OS at all if that fails.

You could try poking at it with ADB Parser and see what you get back. Try doing a Talk to register 3 to show if the keyboard microcontroller is still paying attention at all, or an ADB Reinit to see if it still is detected post-boot.

Might just be some weird software glitch too. Maybe boot off a different system disk and see if the behavior changes?

 

[Arbee]

The power key is both a key readable through the microcontroller and a directly connected switch with a dedicated pin on the ADB connector. So it's possible for it to turn the machine on even if the microcontroller is dead or missing. That said, clearly it's not dead since it works on the SE/30. Maybe the +5V power is off-spec on the Q700?

 

[saybur]

Possibly, but I'd expect that'd manifest as no keyboard detected. Must be some amount of working ADB comms to make TattleTech show it? Definitely very strange!