Keyboard int on QE128

[abicash]

Hello

I am trying to write a code for QE128 which i will explain 

i have 2 keys, A & B

On pressing A , i xmit char '1' on SCI . I don't release A and until this time ,'1' is xmitted continuosly on Tx and an LED glows during this time.While i am pressing down A , if i press B w/o releasing both keys, then char '2' is xmitted and another LED glows.Upon releasing both keys,the process is terminated (LED's off and xmit is off)

For this i wrote a code invoking KBI interrupts.But i found out that after pressing B ,the A routine is serviced as well so as to get 212121... on my terminal.

Can anyone provide a valid approach of doing this?

Awaiting precious replies.

Thanks and regards

[abicash]

Hello

I tried some fundamental things.Which i have attached.I have understood the limitations of KBI too.

With the code attached i find that only on PTA3 being pressed , i dont get any serial out.

Other keys work okay.I am just not able to determine the cause.

Can someone guide me?