Need help in program for remote control using PIC16F84A

[mister_e]

the most inefficient way but easy to follow.

LOW PORTB.4
Key var byte

start:
    Key=(PORTB&$0F) rev 4
    If Key<>4 then Start
    While key 
        Key=PORTB&$0F 
        wend 
    pause 50

    Wait2nd: 
        Key=(PORTB&$0F) rev 4
        if key=0 then Wait2nd
        If Key<>9 then Start
        While key 
            Key=PORTB&$0F 
            wend 
        pause 50

    Wait3rd:
        Key=(PORTB&$0F) rev 4
        if key=0 then Wait3rd
        If Key<>2 then Start
    
    HIGH PORTB.4    
Spin:
    goto spin