> tens wrote:
>
> Hi Piclisters,
>
> I'm newbie in PICs field and still learning for PIC codes..

I haven't tested this but it should work ok. It's written simply, so you
should be able to follow the code.

Contestant buttons connected from ground to PortB pins 0 - 3 with
pullups enabled.
Connect LEDs via 1K resistors to portB pins 4 - 7

        list p=16c84,c=140    ; processor type

status equ 3h
intcon equ 0bh
trisa equ 85h
trisb equ 86h
option_reg equ 81h
t0if equ 2h
temp equ 0ch

          ; 4MHz clock
          ; prescaler set to divide by 32
          ; gives about 8mS delay for mnloop
          ; you can change this to suit your requirements
          ;
          ; -------------
          ; PROGRAM START
          ; -------------
          ;

        org 0h

        clrf porta
        clrf portb
        bsf status,rp0      ; RP 1
        clrf trisa          ; all outputs - not used
        movlw b'00001111'   ; 7 - 5 = LED outputs, 3 - 0 = key inputs
        movwf trisb
        movlw b'00000100'   ; pullups on, prescale 1:32
        movwf option_reg
        bcf status,rp0      ; RP0

        ; maybe put a powerup delay routine here

mnloop  nop             ; wait approx 8mS
        btfss intcon,t0if
        goto mnloop

        bcf intcon,t0if ; reset timer flag
        movf portb,w    ; read portb
        movwf temp      ; store result

        rrf temp        ; if carry clear, key #1 was pressed
        btfc status,carry
        goto Check2

        bsf portb,4     ; contestant 1
        goto Loop

Check2  rrf temp        ; if carry clear, key #2 was pressed
        btfsc status,carry
        goto Check3

        bsf portb,5     ; contestant 2
        goto Loop

Check3  rrf temp        ; if carry clear, key #3 was pressed
        btfsc status,carry
        goto Check4

        bsf portb,6     ; contestant 3
        goto Loop

Check4  rrf temp        ; if carry clear, key #4 was pressed
        btfsc status,carry
        goto mnloop     ; no keys pressed

        bsf portb,7     ; contestant 4

Loop    goto Loop       ; wait here until power down


        end

PS Don't forget to disable the WDT

--
Best regards

Tony

'The Engine' - Design your own programmer.

http://www.picnpoke.com
Email picnpoke@cdi.com.au