Pic16f88

[nonny]

Dear experts,

I am new to this programing. I have a small project which i would like to get help with. Its a small car which should turn ON the lights and turn OFF with two buttons.

Please help me.

Thanks

[mister_e]

Hi and welcome.

try the following

        '
        '       Pic Configuration
        '       =================
        ASM
        IFNDEF PM_USED
            list w=-207
            ;    Program Configuration Register 1
            cfg1 = _INTRC_IO & _WDT_OFF & _PWRTE_ON & _MCLR_OFF & _BODEN_ON & _LVP_OFF & _CCP1_RB0
            cfg2 = _CP_OFF  & _CPD_OFF & _WRT_PROTECT_OFF & _DEBUG_OFF 
            __CONFIG    _CONFIG1, cfg1 & cfg2		    		 
            
            ;    Program Configuration Register 2
            __CONFIG    _CONFIG2, _IESO_OFF & _FCMEN_OFF
            list w=+207
            ELSE
                device  INTRC_OSC_NOCLKOUT, WDT_OFF, PWRT_ON, MCLR_OFF, BOD_ON, LVP_OFF, CCPMX_OFF 
                device  PROTECT_OFF, CPD_OFF, WRT_OFF, DEBUG_OFF    
                device2 FCMEN_OFF, IESO_OFF
            ENDIF
        ENDASM
        OSCCON = %01100000 ' set to 4 MHz clock
        
        '
        '       Hardware configuration
        '       ======================
        TRISB=0     ' Set all PORTB pins to output
        TRISA=255   ' Set all PORTA pins to output
        ANSEL = 0   ' disable adc converters
        CMCON=7     ' disable analog comparator
        
        '
        '       Hardware assignment
        '       ===================
                '       
                '       Push buttons
                '       ------------
                '       Push buttons are connected between PIC i/o and gnd
                '       don't forget to add a pull-up resistor on the i/o too
                '
        ONButton    VAR PORTA.0
        OFFButton   VAR PORTA.1
                '
                '       Light
                '       -----
                '       LED connect between I/O and gnd... with a resistor in serie
                '
        LIGHT       VAR PORTB.0

        '
        '       Hardware initialisation
        '       =======================
        WHILE OSCCON.2=0 : WEND     ' wait 'till internal OSC is stable
        PORTB=0                     ' clear all PORTB i/o 
        
START:
        if ONButton = 0 then
            light = 1   ' turn the LED on
            endif

        if offbutton = 0 then
            light = 0   ' turn the led off
            endif           
            
        GOTO START

[nonny]

thanks a lot, question! the above configs. can be done in the software as well right so i dont need to do those in the coding??

[mister_e]

yes you can do it in your programmer software as well... but you need to set them each time... and remind which one you need to set. Kinda annoying if months/years later you need to reprogram a PIC and you don't remind them.

Once you load the .HEX file to program your PIC, your PIC Programmer software have to be smart enough to refresh the default one and to program them. Careful, some software need to be warned to do so.

I ALWAYS set them in code, it's the right place to fit them.. not in a README.TXT or on a piece of paper sticked somewhere.

But it's me

EDIT: the above are way to much, but as i didn't know which assembler you're using (PM/MPASM) i've just put both and let the compiler choose for you. See the FAQ for more details.

[nonny]

thanks a lot, I will try it out and let you know. another thing forgot to ask. will it work for 4 LEDs or two? e.g. two front two rear...

[nonny]

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