Sep,

-----Original Message-----
From: sep <sseyedi@hypervr.com>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Monday, February 07, 2000 12:29 AM
Subject: problem with code


|Hello,
|RE: PIC16F84
|I am still working on this piece of code and to me it fully makes sense.
But
|the thing wont work. None of the LEDs get lit with the input. I tried it on


Even the LED at RB1 (who is always on)?

|the MLAB simulator and it seems to be doing what I want it to do!
|Anybody see the problem? (or maybe have code for reading a button (or a set
|of), debounce them and light an LED accordingly, this might actually be
more
|faster?!).
|
|
|------
|#include "p16f84.inc"
|
|        LIST P=16F84, R=DEC
|
|
|        ;  Register Usage
|        CBLOCK 0x20                   ;  vars to use for the delay loop
|                LoopCntr1,LoopCntr2
|        ENDC
|
|
|        __CONFIG _CP_OFF & _XT_OSC & _PWRTE_ON  & _WDT_OFF
|        ;  Note that the WatchDog Timer is OFF
|        ;  ** the RC oscillator does not work for some reason with an rc
|oscillator?!?!
|        ;     the funny thing is that the xt works with it though!

???
Which is the source of clock in your micro?(Type and speed)


|
|
|        ; Note: B0 : mommentarily on push button
|        ;       B1 : lit at all times!
|        ;       B2 : lit if button is being pushed
|
|
|        ORG     0
|        GOTO    Start
|
|; DELAY SUBROUTINE
|; - creates a delay by doing (for) loops
|Delay           MOVLW   250
|                MOVWF   LoopCntr1
|Outer           MOVLW   110
|                MOVWF   LoopCntr2
|Inner           NOP
|                NOP
|                DECFSZ  LoopCntr2,F
|                GOTO    Inner
|                DECFSZ  LoopCntr1,F
|                GOTO    Outer
|                RETURN
|


Assuming the micro is running with 4 MHz Xtal, the delay looks fine.


|
|; MAIN PROGRAM
|;
|Start
|        BSF     STATUS,RP0      ; select bank 1
|        MOVLW   0x01            ; turn b0:input, b...:output
|        MOVWF   TRISB           ; apply it to trisb register
|        BCF     STATUS,RP0      ; select bank 0 (come back!)
|        BSF     PORTB,1         ; turn on led on B1 (and keep lit)
|
|
|Loop
|        BTFSS   PORTB,0         ; Is the Button Pressed? (if PORTB<0>=0then
... )
|        GOTO    ButtonPressed   ;  .... turn it on
|        BCF     PORTB,2         ; (else:) Turn off LED B2 off
|        GOTO    Loop
|
|ButtonPressed                   ; Button Pressed, Turn LED on
|        BSF     PORTB,2
|        CALL    Delay
|        GOTO    Loop
|
|        END                     ; end of program.
|------
|
|Thanks.
|
|+----------------------------+
||  Sep Seyedi   [:{0)]       |
|+----------------------------+


Are You setting correctly the programmer? An what about Your hardware? Is
the input
pin RB0 connected correctly to the pullup, and the swith to GND?

Regards,

S.-