Interrupt stack overflow problem with Resume {label}

[Yuantu Huang]

Dear All,

My application needs interrupt using "Resume Label" statement to do the special job. However, it can only do 27 times for me, then resets doing 27 times job again, and then stops working. After reading the PBP Manual and Melanie' thread posted on 14th April 2004, I think it may be the stack overflow problem and do not know how to fix.

I believe that the PBP Forums can give the suggestion and help to solve the problem.

The testing code using PIC18F4525 is below and also attached.

' The following program may suffer interrupt stack overflow problem.
' Reset after Counter == 27 for the first time,
' and then die when Counter == 27 for the second time
'
' Target:PIC18F4525
' The following configuration bits were used
' __CONFIG _CONFIG1H,_OSC_INTIO67_1H
' __CONFIG _CONFIG2L, _PWRT_ON_2L & _BORV_27_2L
' __CONFIG _CONFIG2H, _WDT_ON_2H & _WDTPS_128_2H
' __CONFIG _CONFIG3H, _MCLRE_ON_3H & _PBADEN_OFF_3H
' __CONFIG _CONFIG4L, _LVP_OFF_4L & _ENHCPU_OFF_4L

DEFINE OSC 8

; LCD definition
define LCD_DREG PORTD
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTD
DEFINE LCD_RSBIT 4
' Make LCD display in 4 line mode
DEFINE LCD_LINES 4
' Set LCD Enable port
DEFINE LCD_EREG PORTD
' Set LCD Enable bit
DEFINE LCD_EBIT 5

Counter var word

' Init internal clock and others
OSCCON = %01110111 ' Use internal 8MHz clock
ADCON1 = %00001111 ' Disable A/D convertor
TRISD = %00000000 ' PORTD Set as outputs
INTCON = %10100000 ' Enable global interrupt
' Enable Timer0 overflow interrupt
T0CON = %00010111 ' Set 1:256 prescale
TMR0L = 0 ' Make a second interval using TMR0L & TMR0H to
TMR0H = 223 ' interrupt every second or so
T0CON.7 = 1 ' Enable Timer0
'RCON = 1 ' no effect, 0 or 1 got the same result


counter = 0
Pause 2000 ' Wait for LCD and PIC to startup (tested: 1000-10000)
LCDOUT $FE, 1, #Counter

'clearwdt ' no effect
goto MainLoop

' Interrupt subroutine
Disable
CounterISR:
Counter = Counter + 1
TMR0L = 0
TMR0H = 223 ' Set one second interval
INTCON.2 = 0 ' Make the timer0 interrupt again
resume Location ' If remove Location,
' counter is right & PIC never reset or die
resume
Enable

on interrupt goto CounterISR

Location:
LCDOUT $FE, 1, #Counter

MainLoop:
pause 1 ' If comment it out, reset forever, why?
goto MainLoop

end

Thank you for your help