Get all possible digital outputs on a PIC18F2*50

Recently I've been experimenting with a PIC18F2550 microcontroller and it wasn't easy at all to get the ports running in the mode I wanted to. So at first, I looked through the datasheet to find out which ports can be used as digital output pins and how to configure them. This is what I came up with:

Available output pins:

• PORTA: RA0 through RA6 gives 7 outputs
• PORTB: RB0 through RA7 gives 8 outputs
• PORTC: RC0 through RC2, RC6 & RC7 gives 5 outputs

=> on a PIC18F2*50 you have 20 digital outputs total.

Configure options:

• FOSC = INTOSCIO_EC //using the internal oscillator will free pins RA5 and RA6
• LVP = OFF //you don't have to ground RB5 anymore
• PBADEN = OFF //disable the analog inputs on RB0 through RB4
• DEBUG = OFF //disable debug output, free RB6 and RB7

Registers to set:

• ADCON1 = 0x0F; //disable analog inputs on RA0 through RA3

One comment on using RB6 & RB7: You'll have to interface these pins over at least 10k resistors to be able to do ICSP programming on these pins. If you can avoid it, don't use these pins for I/O in your circuit.

Testing code:

#include <p18cxxx.h>

#pragma config MCLRE = ON             //MCLR pin enabled; RE3 digital input disabled
#pragma config WDT = OFF              //HW Disabled - SW Controlled
#pragma config BOR = OFF              //Brown-out Reset disabled in hardware and software

#pragma config FOSC = INTOSCIO_EC     //Internal oscillator, port function on RA6, EC used by USB
#pragma config LVP = OFF              //Single-Supply ICSP disabled, free RB5
#pragma config PBADEN = OFF           //RB0 through RB4 pins are configured as digital I/O on reset
#pragma config DEBUG = OFF            //Background debugger disabled, RB6 and RB7 configured as I/O pins on reset

void main ( void );
void init ( void );

void init (void)
{
    OSCCON = 0xFF;    //8MHz internal clock
                      //1ms = 2000000 Instructions
    ADCON1 = 0x0F;    //Set multiplexed pins on PORTA to digital
    TRISA = 0x00;     //Configure RA0 through RA6 as output
    TRISB = 0x00;     //Configure PORTB as output
    TRISC = 0x00;     //Configure RC0:RC3, RC6:RC7 as output
    LATA = 0x00;      //Reset Pins
    LATB = 0x00;
    LATC = 0x00;
}

void main (void)
{
    init();

    LATA = 0x7F;     //01111111
    LATB = 0x3F;     //00111111
    LATC = 0xC7;     //11000111

    while (1) {}
}

Result

My PIC18F2550 controlling 18 low-current (!) LED independently. RC6 and RC7 were needed for ICSP.
The maximum rated current per Pin is 20mA, Vss (Ground) can only handle 200mA. Caution: Using standard LED would fry the ports!