thanks for your reply but there is all ready a interrupt service routine for keypresses, my problem is i need 2 keypresses for 1 rtc (bcd) byte, the user types in (for example) keypress1 = 1 (0x31) and keypress2 = 2 (0x32)

this needs to be converted to 0x12 (bcd) for rtc,

thats no problem, ive sussed how to do that as posted in the code, my problem is how do i process both keypresses, so do i get 1st keypress, then wait in while loop for second keypress, "OR" the 2 bytes to get one byte for rtc, im just not too sure how to tie this in so the flow is right.

is this making sense, i know what i mean, just not sure if someone reading this will understand.

basically i need to convert 16bits hex to 8bit byte, then send 8bit byte to rtc, its the 16bits, thats 2 keypresses, hmmm i will try more to think, any help would be appreciated

thanks

luigi