Now it's ok ?
Code:
   '// Define port pins as inputs and outputs ...
   TRISA  = %00000111
   TRISB  = %00000000


include "c:\pbp\keypad2.pbp" ' see http://www.picbasic.co.uk/forum/showthread.php?t=3250

main:
gosub keypadscan
gosub check
goto main

check:
select case key 
case 1     ; volume down
portb.2=0
pause 500 ; i put the resistor on portb.2 to ground for 0.5 sec
portb.2=1