I don't post much but last night I was work on finalizing a hserin interrupt routine for a project I'm working on. I'm using pic18f4431 portb.5 as an output for a buzzer on my main board. I normally just hook my scope to a jumper pin for portb.5 to monitor as a heart beat. Anyway I've used this main board in many projects so I know there are no hardware issues. But for some reason after testing the hserin routine portb.5 stopped working. I've tried everything I know, I wrote a simple program just to toggle portb.5 and portb.6. Portb.5 nothing sitting at zero volts portb.6 10ms square wave. I've tried a new chip as well and I can't seem to get this running. I haven't seen this before but the fact that even a new chip won't work leads me to believe some obscure setting is wrong and can't find it. The crazy thing is that I loaded my original code back to the board and portb.5 no longer works. So it has to be a setting of some sort.

If anyone can help me get this going I'll post a full project and video of a large feed to length automated machine I'm finishing up. Thanks

Little test program:
Code:
;----[18F4431 Hardware Configuration]-------------------------------------------
#IF __PROCESSOR__ = "18F4431"
  #DEFINE MCU_FOUND 1
#CONFIG
  CONFIG  OSC=XT, FCMEN=OFF, IESO=OFF, PWRTEN=OFF, BOREN=OFF, BORV=20, WDTEN=OFF
  CONFIG  WDPS=512, WINEN=OFF, PWMPIN=OFF, LPOL=HIGH, HPOL=HIGH, T1OSCMX=OFF
  CONFIG  FLTAMX=RC1, SSPMX=RC7, PWM4MX=RD5, EXCLKMX=RC3, MCLRE=ON, STVREN=ON
  CONFIG  LVP=OFF, DEBUG=OFF, CP0=OFF, CP1=OFF, CP2=OFF, CP3=OFF, CPB=OFF
  CONFIG  CPD=OFF, WRT0=OFF, WRT1=OFF, WRT2=OFF, WRT3=OFF, WRTC=OFF, WRTB=OFF
  CONFIG  WRTD=OFF, EBTR0=OFF, EBTR1=OFF, EBTR2=OFF, EBTR3=OFF, EBTRB=OFF
#ENDCONFIG

#ENDIF

;----[Verify Configs have been specified for Selected Processor]----------------
;       Note: Only include this routine once, after all #CONFIG blocks
#IFNDEF MCU_FOUND
  #ERROR "No CONFIGs found for [" + __PROCESSOR__ +"]"
#ENDIF


 
'---[OSCILATORS]----------------------------------------------------------------
 DEFINE OSC 8
 OSCTUNE = %00000000	  
 OSCCON = %01111000       

'---[CAPTURE COMPAIR MODUALS]---------------------------------------------------
CCP1CON = %00000000   
CCP2CON = %00000000
'-------------------------------------------------------------------------------
'---[ANALOG CHANELS TO DIGITAL]-------------------------------------------------
ANSEL0 = %00000000          
ANSEL1 = %00000000          
ADCON0 = %00000000
'---[CONFIGURE PORT]------------------------------------------------------------
 TRISB = %00000000
  LATB = %00000000
 PORTB = %00000000
'-------------------------------------------------------------------------------         
'---[ Alias ]-------------------------------------------------------------------
BUZZER VAR PORTB.5
BUZZER2 VAR PORTB.6
'---[ MAIN PROGRAM]-------------------------------------------------------------
MAIN:
TOGGLE BUZZER
TOGGLE BUZZER2
PAUSE 10
GOTO MAIN
END