Hi, Even to simulate multiple function gpio, it's necessary set up in OPTION menu, then HARDWARE. Note, in hardware window, to select internal oscilator, enable stimulus on gpio(clkin; clkout). Clear the tick on Mclr enable gpio on this pin. This is necessary in all 12cxxx , an 16c505 and all multiple function gpio. -----Mensagem original----- De: Glen Data: Domingo, 23 de Maio de 1999 02:12 Assunto: mplab-step prob? >hi & thanks for your time, > >i'm using mplab to step through a program for a 12c508a.(using step) >i get to the part of code to test for zero crossing.(code below) > >chcycs btfsc gpio,3 ;check for 0 > goto chcycs >lw btfss gpio,3 ;check for 1 > goto lw > >when i get to chcycs it just locks into chcycs. >even when i use step over it still does the same , gets locked ! > >how do i get past these 2 loops to keep checking the rest of the >program. >i've tried stimulus pins but didn't work ! > >i've been reading mike predkos book "programming & customising the pic >microcontroller" & shows how to use dos sim. > >i'm having trouble with the windows simulator. > >any good information on how to use windows mplab. >a decent tutorial would be good. > >thankyou for your time >glen >