no problem so far.
in an other routine i want to increase or decrease a value when i press the up or down keys. but when 1 press these keys at the same time my program doesn't respond any more.
the keyboard is attached to an interrupt port. does someone knows where i can find a sollution for this problem or how to solve this problem??

a couple of guesses
1) do you call a function to "increase or decrease a value when i press the up or down keys" and is that function also called outside the interrupt.
2) does it work if you tap the key twice, but not if you hold the key?
3)Is the "vlaue" 8 bits or longer?

Erik