(Darn, I just typed out a huge message, and when I submitted- it disappeared!)
I've recently acquired an Apple II Plus- and when I turn it on, the power light lights, the speaker beeps, and I see Apple II on the screen and a blinking cursor. However, the keyboard doesn't provide any input- except for CTRL-RESET works. No other keys work.
I've googled a bit- reseated any related chip I could find, verified continuity between keyboard encoder board pins and keyboard, keyboard ribbon cable, etc. No avail.
Can anyone point me to documentation of how the encoder is supposed to work? For example, a closed key switch- how is this "read" by the encoder, and what is sent through the ribbon cable to the motherboard?