Re: weird 97 keyboard behaviour Message #5 Posted by Tony Duell (UK) on 10 July 2002, 6:48 p.m., in response to message #1 by jose goncalves
There is no obvious 'separation' between the 2 halves of the keyboard in the _electrical_ diagram of the matrix, although (electrical) rows of 4 keys are often either all from the left side or all from the right side. Do you get all the display digits appearing correctly (use the COS key or someting to get a display will 10 digits). If the display is fine, then the keyboard must be being scanned correctly (the same chip -- 'cathode driver' -- handles both).
For much the same reason it can't be a bad connection between the CPU board and the keyboard -- that would take out an entire column, which would include keys from both parts of the keyboard).
My guess is a mechanical problem with the keyboard. Take it apart (after removing the keyboard/display from the top case, take out all the screws on the back and lift off the PCB. Then remove the
insulators and the contact sheets. Look for coffee spills (!) and check that the parts are assembled correctly. One insulator either side of the contact sheet, contact sheet with the convex surface towards the keys.
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