Using RA5 in PIC16F1455 as digital output on XC8 compiler

Question

I am trying to get RA5 as digital output. But it does not seem to work. I went through the datasheet and found RA0, RA1 and RA3 are input only. That means RA5 supports both input and output, am I right? Why I can't get RA5 to output digital 1?

void main() {
    ANSELA = 0x00;  // PORTA digital setup
    ANSELC = 0x00;  // PORTC digital setup
    TRISA = 0x00;   // PORTA all outputs
    TRISC = 0x00;   // PORTC all outputs
    LATA = 0xFF;    // PORTA all high
    LATC = 0xFF;    // PORTC all high
    while (1) {
    }
}

All other pins except RA0, RA1 and RA3 can output digital high without any problem. — retromuz, Sep 26 '15 at 03:27
Can you show the settings of your configuration bits? `RA5` may have been allocated as a clock or timer input. — Roger Rowland, Sep 26 '15 at 07:46
I copied config bits from one of my other projects and it started working fine! — retromuz, Sep 29 '15 at 21:30

score 0 · Accepted Answer · answered Sep 29 '15 at 21:33

I copied configuration bits from my other project as @Roger suggested.

Having below configuration bits solved the matter.

// CONFIG1
#pragma config FOSC = INTOSC    // Oscillator Selection Bits (INTOSC oscillator: I/O function on CLKIN pin)
#pragma config WDTE = OFF       // Watchdog Timer Enable (WDT disabled)
#pragma config PWRTE = OFF      // Power-up Timer Enable (PWRT disabled)
#pragma config MCLRE = OFF      // MCLR Pin Function Select (MCLR/VPP pin function is Digital Input)
#pragma config CP = OFF         // Flash Program Memory Code Protection (Program memory code protection is disabled)
#pragma config BOREN = ON       // Brown-out Reset Enable (Brown-out Reset enabled)
#pragma config CLKOUTEN = OFF   // Clock Out Enable (CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin)
#pragma config IESO = OFF       // Internal/External Switchover Mode (Internal/External Switchover Mode is enabled)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable (Fail-Safe Clock Monitor is enabled)

// CONFIG2
#pragma config WRT = OFF        // Flash Memory Self-Write Protection (Write protection off)
#pragma config CPUDIV = NOCLKDIV // CPU System Clock Selection Bit (CPU system clock divided by 6)
#pragma config USBLSCLK = 48MHz // USB Low SPeed Clock Selection bit (System clock expects 48 MHz, FS/LS USB CLKENs divide-by is set to 8.)
#pragma config PLLMULT = 4x     // PLL Multipler Selection Bit (3x Output Frequency Selected)
#pragma config PLLEN = ENABLED  // PLL Enable Bit (3x or 4x PLL Enabled)
#pragma config STVREN = ON      // Stack Overflow/Underflow Reset Enable (Stack Overflow or Underflow will cause a Reset)
#pragma config BORV = LO        // Brown-out Reset Voltage Selection (Brown-out Reset Voltage (Vbor), low trip point selected.)
#pragma config LPBOR = OFF      // Low-Power Brown Out Reset (Low-Power BOR is disabled)
#pragma config LVP = OFF         // Low-Voltage Programming Enable (Low-voltage programming enabled)

Using RA5 in PIC16F1455 as digital output on XC8 compiler

1 Answers1