The KBI does not function in a P89LPC921F but it functions in the P89LPC925F.
In the 921 the KBPATN always has a value of "0FFH" and the KBMASK always has a value of "00". If I write the registers and read back the value, it is unchanged. I assume that since the KBMASK is "00", that is why an interrupt never occurs. Is anyone else aware of this problem.