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PIC blinked

pic16f887/pic16f877a & pic16f18877

With a few changes, code for 877A can be easily transferred to 887 (as for any PIC, datasheet reading is necessary). 887 has internal oscillator, it is cheaper than 877A, …

Blinking LED

First, use the compiler to generate hex;
Then, use protelus to draw “Schematic Capture”;
Finally, import the hex file into the MCU component.

16F887

We are using Proteus simulator for simulating our code but if you are testing the code in real world test bench all you need is,

PIC16F887 or PIC16F877A
LED
330R Resistor
4Mhz Crystal
After wiring LED and crystal to the microcontroller and giving the proper supply connections, you are good to start.

LIST p=16F887			 ;tell assembler what chip we are using
INCLUDE <P16F887.INC>
 
 __CONFIG  _CONFIG1, _INTOSCIO & _WDT_OFF & _PWRTE_ON & _MCLRE_ON & _CP_OFF & _CPD_OFF & _BOR_OFF & _IESO_OFF & _FCMEN_OFF & _LVP_OFF & _DEBUG_ON


CBLOCK h'20'
    COUNT1
    COUNT2
ENDC
    ORG		0x00

MAIN:
    BANKSEL		TRISB
    BCF 	    TRISB,0     
    BANKSEL		PORTB
MainLoop:
    BCF		    PORTB,0
    CALL		DELAY3
    BSF			PORTB,0 
    CALL		DELAY3
    GOTO	    MainLoop            ; Do it again...


DELAY3:
    DECFSZ		COUNT1,1
    GOTO		DELAY3
    DECFSZ		COUNT2,1
    GOTO		DELAY3
    RETURN

END

load hex

16F18877

    title "Blink V. 1.0"
    subtitle "The uC Equivalent of Hello world"

; ***** Program Header *******************************************************************************
    list P=PIC16F18877, ST=OFF, MM=OFF, N=42, B=4, W=1 ; <-- List file directives
    include <p16f18877.inc> ; <--Use the name of your PIC here

; ***** Device Configuration *************************************************************************
    __CONFIG _CONFIG1, _FEXTOSC_OFF & _RSTOSC_HFINT32 & _CLKOUTEN_OFF & _CSWEN_ON & _FCMEN_ON
    __CONFIG _CONFIG2, _MCLRE_ON & _PWRTE_OFF & _LPBOREN_OFF & _BOREN_OFF & _BORV_LO & _ZCD_OFF & _PPS1WAY_OFF & _STVREN_ON
    __CONFIG _CONFIG3, _WDTCPS_WDTCPS_31 & _WDTE_OFF & _WDTCWS_WDTCWS_7 & _WDTCCS_SC
    __CONFIG _CONFIG4, _WRT_OFF & _SCANE_available & _LVP_ON
    __CONFIG _CONFIG5, _CP_OFF & _CPD_OFF

    CBLOCK h'20'
        COUNT1
        COUNT2
    ENDC
    ORG     0x00

MAIN:
    BANKSEL     TRISB
    BCF         TRISB,0
    CALL        Init_Osc
    BANKSEL     PORTB

MainLoop:
    BCF         PORTB,0
    CALL        DELAY3
    BSF         PORTB,0 
    CALL        DELAY3
    GOTO        MainLoop            ; Do it again...

; Initialize the PIC Oscillator.
; For the 16F18877, 
; page 122 of the data sheet(F version), the OSCCON1 register. 
; Set according to Table 6-1(NOSC/COSC Bit Settings) and Table 6-2(NDIV/CDIV Bit Settings): 
;  Clock Source: HFINTOSC(110)
;  Clock divider: 8(0011)
; Our byte now looks like this x1100000(0x60) - 32 Mhz.
; Our byte now looks like this x1100001(0x61) - 16 Mhz.
; Our byte now looks like this x1100010(0x62) - 8 Mhz.
; Our byte now looks like this x1100011(0x63) - 4 Mhz.
; Our byte now looks like this x1100100(0x64) - 2 Mhz.
; Our byte now looks like this x1100101(0x65) - 1 Mhz.
; Our byte now looks like this x1100110(0x66) - 500 kHz.
; Our byte now looks like this x1100111(0x67) - 250 kHz.
; Our byte now looks like this x1101001(0x68) - 125 kHz.
Init_Osc:          ; System oscillator set to 4MHz
    banksel OSCCON1
    movlw   0x63
    movwf   OSCCON1
    RETURN

DELAY3:
    DECFSZ      COUNT1,1
    GOTO        DELAY3
    DECFSZ      COUNT2,1
    GOTO        DELAY3
    RETURN

    END

Ref