PIC16F887 LED scrolling programming with XC8

When getting started with microcontroller programming, we usually playing with simple LEDs. A common things is LED blinking, chasing, scrolling etc.

Five colors of 3 mm LEDs.

In program C, scrolling LEDs made easy by using the binary shift operation. There is no carry bit in this operation. There are two directions of shifting:

1. shift left "<<"
2. and shift right ">>"

In this example, I use PortD for outputting the shifting LEDs.

PIC16F887 supplied at +5V DC.
External crystal of 4 MHz fed the PIC device.
SW1 uses to hard reset the MCU.
bar graph LED displays the scrolling. 

Source code is written using XC8 C compiler:

#include<xc.h>
// PIC16F887 Configuration Bit Settings
// CONFIG1
#pragma config FOSC = XT
#pragma config WDTE = OFF
#pragma config PWRTE = OFF
#pragma config MCLRE = ON
#pragma config CP = OFF
#pragma config CPD = OFF
#pragma config BOREN = ON
#pragma config IESO = ON
#pragma config FCMEN = ON
#pragma config LVP = ON
// CONFIG2
#pragma config BOR4V = BOR40V
#pragma config WRT = OFF
/*_XTAL_FREQ use for __delay*/
#define _XTAL_FREQ 4000000
#define blinkRate 100
void main(){
    //Clear PortD
    PORTD=0x00;
    //Set PortD To Output
    TRISD=0x00;
    while(1){
        PORTD=0x01;
        
        while(PORTD!=0){
            __delay_ms(blinkRate);
            PORTD<<=1;
        }
        PORTD=0x80;
        while(PORTD!=0){
            __delay_ms(blinkRate);
            PORTD>>=1;
        }
    }
}

A screen shot of the simulation.

A screen shot of the simulation.
PortD outputs to bar graph LED display.

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