Slight update. It is RB5/PGM and not RB4 that crasches the program
if it floats. Any LED connected to it is off all the time, when the rest of
the LEDS on port B cycles repeatedly.

Generally its a bad idea to leave pins floating, but this one is set as
output
so it shouldnt make the PIC restart, right?

/PJ


// This is example 1 from "Getting Started with MPLAB C18"
#include <p18F458.h>  /* for TRISB and PORTB declarations */
#include <delays.h>   /* for 'Delay10KTCYx'      */
int counter;
int LEDout;

void main (void)
{
 TRISB = 0;             /* configure PORTB for output */
 TRISD = 0;             /* configure PORTD for output */
 PORTB = 0;    /* set all 8-bits low */
    counter = 1;
 LEDout=0;
 PORTB = LEDout;   // display value of 'counter' on the LEDs
 Delay10KTCYx (255);  // pause for a moment (255 * 10,000 cycles)
 Delay10KTCYx (255);  // pause for a moment (255 * 10,000 cycles)
 Delay10KTCYx (255);  // pause for a moment (255 * 10,000 cycles)

 while(1)
 {
 while (counter <= 8)
 {
  if (counter>=1) LEDout=1;
  if (counter>=2) LEDout=2;
  if (counter>=3) LEDout=4;
  if (counter>=4) LEDout=8;
  if (counter>=5) LEDout=16;
  if (counter>=6) LEDout=32; //<-this is where it fails
  if (counter>=7) LEDout=64;
  if (counter>=8) LEDout=128;
  PORTB = LEDout;  // display value of 'counter' on the LEDs
  Delay10KTCYx (255); // pause for a moment (255 * 10,000 cycles)
  counter++;
    }
 counter = 1;   // reset counter for for next cycle
 }      // END-LOOP: while(1);
}

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