1
\$\begingroup\$

I am trying to run the simple hello world program for a PIC18F4550 using the XC8 compiler. I am really new on pic microcontrollers.

My code is the next:

#include <stdio.h>
#include <stdlib.h>
#include "blinking_led.h"


void main(void) {

    TRISBbits.RB0 = 0; //Setting PORTB.0 as output

    while (1)
    {
        LATBbits.LATB0 = 1; //Switching PORTB.0 on           
    }

    return;

}

And I am using the next blinking_led.h header created using the configuration bits

// PIC18F4550 Configuration Bit Settings

// 'C' source line config statements

// CONFIG1L
#pragma config PLLDIV = 1       // PLL Prescaler Selection bits (No prescale (4 MHz oscillator input drives PLL directly))
#pragma config CPUDIV = OSC4_PLL6// System Clock Postscaler Selection bits ([Primary Oscillator Src: /4][96 MHz PLL Src: /6])
#pragma config USBDIV = 1       // USB Clock Selection bit (used in Full-Speed USB mode only; UCFG:FSEN = 1) (USB clock source comes directly from the primary oscillator block with no postscale)

// CONFIG1H
#pragma config FOSC = EC_EC     // Oscillator Selection bits (EC oscillator, CLKO function on RA6 (EC))
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)
#pragma config IESO = OFF       // Internal/External Oscillator Switchover bit (Oscillator Switchover mode disabled)

// CONFIG2L
#pragma config PWRT = OFF       // Power-up Timer Enable bit (PWRT disabled)
#pragma config BOR = ON         // Brown-out Reset Enable bits (Brown-out Reset enabled in hardware only (SBOREN is disabled))
#pragma config BORV = 3         // Brown-out Reset Voltage bits (Minimum setting 2.05V)
#pragma config VREGEN = OFF     // USB Voltage Regulator Enable bit (USB voltage regulator disabled)

// CONFIG2H
#pragma config WDT = ON         // Watchdog Timer Enable bit (WDT enabled)
#pragma config WDTPS = 32768    // Watchdog Timer Postscale Select bits (1:32768)

// CONFIG3H
#pragma config CCP2MX = ON      // CCP2 MUX bit (CCP2 input/output is multiplexed with RC1)
#pragma config PBADEN = ON      // PORTB A/D Enable bit (PORTB<4:0> pins are configured as analog input channels on Reset)
#pragma config LPT1OSC = OFF    // Low-Power Timer 1 Oscillator Enable bit (Timer1 configured for higher power operation)
#pragma config MCLRE = ON       // MCLR Pin Enable bit (MCLR pin enabled; RE3 input pin disabled)

// CONFIG4L
#pragma config STVREN = ON      // Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
#pragma config LVP = ON         // Single-Supply ICSP Enable bit (Single-Supply ICSP enabled)
#pragma config ICPRT = OFF      // Dedicated In-Circuit Debug/Programming Port (ICPORT) Enable bit (ICPORT disabled)
#pragma config XINST = OFF      // Extended Instruction Set Enable bit (Instruction set extension and Indexed Addressing mode disabled (Legacy mode))

// CONFIG5L
#pragma config CP0 = OFF        // Code Protection bit (Block 0 (000800-001FFFh) is not code-protected)
#pragma config CP1 = OFF        // Code Protection bit (Block 1 (002000-003FFFh) is not code-protected)
#pragma config CP2 = OFF        // Code Protection bit (Block 2 (004000-005FFFh) is not code-protected)
#pragma config CP3 = OFF        // Code Protection bit (Block 3 (006000-007FFFh) is not code-protected)

// CONFIG5H
#pragma config CPB = OFF        // Boot Block Code Protection bit (Boot block (000000-0007FFh) is not code-protected)
#pragma config CPD = OFF        // Data EEPROM Code Protection bit (Data EEPROM is not code-protected)

// CONFIG6L
#pragma config WRT0 = OFF       // Write Protection bit (Block 0 (000800-001FFFh) is not write-protected)
#pragma config WRT1 = OFF       // Write Protection bit (Block 1 (002000-003FFFh) is not write-protected)
#pragma config WRT2 = OFF       // Write Protection bit (Block 2 (004000-005FFFh) is not write-protected)
#pragma config WRT3 = OFF       // Write Protection bit (Block 3 (006000-007FFFh) is not write-protected)

// CONFIG6H
#pragma config WRTC = OFF       // Configuration Register Write Protection bit (Configuration registers (300000-3000FFh) are not write-protected)
#pragma config WRTB = OFF       // Boot Block Write Protection bit (Boot block (000000-0007FFh) is not write-protected)
#pragma config WRTD = OFF       // Data EEPROM Write Protection bit (Data EEPROM is not write-protected)

// CONFIG7L
#pragma config EBTR0 = OFF      // Table Read Protection bit (Block 0 (000800-001FFFh) is not protected from table reads executed in other blocks)
#pragma config EBTR1 = OFF      // Table Read Protection bit (Block 1 (002000-003FFFh) is not protected from table reads executed in other blocks)
#pragma config EBTR2 = OFF      // Table Read Protection bit (Block 2 (004000-005FFFh) is not protected from table reads executed in other blocks)
#pragma config EBTR3 = OFF      // Table Read Protection bit (Block 3 (006000-007FFFh) is not protected from table reads executed in other blocks)

// CONFIG7H
#pragma config EBTRB = OFF      // Boot Block Table Read Protection bit (Boot block (000000-0007FFh) is not protected from table reads executed in other blocks)

// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.

#include <xc.h>

I believe that I am using the registers TRIS and LAT fine. I don't understand why when I simulate it on Proteus doesn't turn on anything

enter image description here

Maybe is something related with the configuration bits, but I am not sure, please help

\$\endgroup\$
  • 3
    \$\begingroup\$ Either set MCLR off in the config bits or put a pull-up to Vdd on pin 1, and also set WDT = OFF to disable the watchdog. Does that change things? You may need to check your oscillator config too. \$\endgroup\$ – Roger Rowland Feb 11 '17 at 6:53
  • 1
    \$\begingroup\$ You are right, I needed to set MCLR off. Thanks a lot \$\endgroup\$ – DieDauphin Feb 11 '17 at 17:15
  • 3
    \$\begingroup\$ You already got the answer and some hints. One other for the future: There's a pitfall with pin A4: It can't source current, only sink. If you connect your LED to A4 as you did here, it will never light up. Instead, connect the LED between positive voltage and A4 to get it working. \$\endgroup\$ – sweber Feb 11 '17 at 17:42
  • 1
    \$\begingroup\$ @RogerRowland - Good catch. Since your suggestion turned out to be the answer, do you want to "upgrade" your comment and re-write it as an answer as well, so we can mark this as answered? \$\endgroup\$ – SamGibson Feb 13 '17 at 13:07
1
\$\begingroup\$

Either set MCLR off in the config bits or put a pull-up to Vdd on pin 1, and also set WDT = OFF to disable the watchdog. Does that change things? You may need to check your oscillator config too.

| improve this answer | |
\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.