Hi, im relatively new to programming and I just need some quick help. I have the pickit 2 with an included pic16f690. I have been trying to create a simple program that will simply blink an LED on and off continuously. It seems to build successfully but when i program it into the micro, it turns on and then blinks off twice before staying on the rest of the time. So it's not looping the way it should. I've done a lot of troubleshooting but I just can't seem to find the problem. If you guys need any more information let me know. Any help is much appreciated

Here's my code:

list p=16f690
#include <p16F690.inc>
__config (_INTRC_OSC_NOCLKOUT & _WDT_OFF & _PWRTE_OFF & _MCLRE_OFF & _CP_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF)
org 0

;CONSTANTS

STATUS equ 03h
TRISC equ 87h
PORTC equ 07h
COUNT1 equ 08h ;08h and 09h are "unimplemented"
COUNT2 equ 09h

;SET UP PORTS

bsf STATUS,5 ;switch to Bank 1
movlw B'000000000' ;sets PORTC all to output
movwf TRISC
bcf STATUS,5 ;switch back to Bank 0

START
movlw B'00000001' ;moves value into w register
movwf PORTC ;from w to PORTC causing the LED to go LOW
Call DELAY ;goes through DELAY subroutine
movlw B'00000000' ;moves value into w register
movwf PORTC ;from w to PORTC causing the LED to go HIGH
Call DELAY
goto START

;Delay Subroutine

DELAY
LOOP
decfsz COUNT1,1 ;Counts down by 1 from 255
goto LOOP ;when COUNT1 is 0, it skips to LOOP2
LOOP2
decfsz COUNT2,1 ;so overall counts down from 255 255 times
goto LOOP ;when COUNT2 is 0, it returns to the main code
return

end

 

STATUS equ 03h
TRISC equ 87h
PORTC equ 07h
COUNT1 equ 08h ;08h and 09h are "unimplemented"
COUNT2 equ 09h

There's no need to define the first 3. Don't use 08h and 09h, start at 20h for your variables.

 

If I were you, I'd try this delay routine:

Delay
Loop1 decfsz COUNT1,1;
. goto Loop1;
. decfsz COUNT1,1;
. goto Loop1;

This is the standard delay loop for PIC ASM and it has always worked for me. It's definitely worth a go
Good luck!
Der Strom

P.S. Don't mind the periods

 

START
movlw B'00000001' ;moves value into w register
movwf PORTC ;from w to PORTC causing the LED to go LOW
Call DELAY ;goes through DELAY subroutine
movlw B'00000000' ;moves value into w register
movwf PORTC ;from w to PORTC causing the LED to go HIGH
Call DELAY
goto START

By the way, you have your "High"s and "Low"s backwards. A 1 means high, a 0 means low.

 

Go here and download this
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en023805
PICkit 2 Starter Kit Lessons
Low Pin Count User's Guide