Another way that has no PAUSE statements, so has very quick
response to all inputs.

; Assumes 20 Mhz Oscillator

T0CON =$86


LOOP:

IF INTCON.2 = 1 THEN
INTCON.2 = 0
TMR0H = $69
TMR0L = $7A
GOSUB SecondsTimer
EndIF

'Run regular code here (check for inputs, timeouts, etc)

GOTO LOOP

SecondsTimer:
Seconds = Seconds + 1
IF Seconds >= 60 THEN
Seconds = 0
Minutes = Minutes + 1
IF Minutes >=60 THEN
Minutes = 0
Hours = Hours + 1
ENDIF
ENDIF
RETURN

END