Still no go :(

Here's what I have verbatim:

***************************************************************

 org 0

  goto MAIN

 org 4

ISR
  MOVWF W_TEMP ;Copy W to TEMP register
  SWAPF STATUS,W ;Swap status to be saved into W
  CLRF STATUS ;bank 0, regardless of current bank, Clears IRP,RP1,RP0
  MOVWF STATUS_TEMP ;Save status to bank zero STATUS_TEMP register
  MOVF PCLATH, W ;Only required if using pages 1, 2 and/or 3
  MOVWF PCLATH_TEMP ;Save PCLATH into W
  CLRF PCLATH ;Page zero, regardless of current page

  bcf INTCON,T0IF

  MOVF PCLATH_TEMP, W ;Restore PCLATH
  MOVWF PCLATH ;Move W into PCLATH
  SWAPF STATUS_TEMP,W ;Swap STATUS_TEMP register into W
  ;(sets bank to original state)
  MOVWF STATUS ;Move W into STATUS register
  SWAPF W_TEMP,F ;Swap W_TEMP
  SWAPF W_TEMP,W ;Swap W_TEMP into W
  retfie

;-----------------------------------------------------------------------
-----------------
; Mainline
;-----------------------------------------------------------------------
-----------------

MAIN
  BANK1                                         ; set up registers
  movlw 0x85                                    ; W <- 1000 0101
  movlw OPTION_REG ^ 0x80                       ; set OPTION_REG
(prescalar=64, no _RBPU)
  BANK0

  clrf TMR0
  clrf INTCON
  bsf INTCON,T0IE
  bsf INTCON,GIE

; VARIOUS VARIABLE INITIALIZATION

  LCD_INITIALIZATION                            ; setup the LCD for
us...
  LCD_CLEAR                                     ; clear it out

TESTLOOP
  DELAY_MILLI 100
  movf TMR0,w
  call LCD_OUT_DATA
  LCD_PRINT 'A'
;  LCD_CLEAR
  goto TESTLOOP

***************************************************

Cut and dry, once everything is set up, I output the TMR0 value (comes
out in HEX) to my LCD, along w/a test character to make sure it's alive.
The HEX changes with every startup, but never changes during my looping,
I always get some random HEX value, and an 'A' printed...

I've also tried adding a variable, having the ISR increment that
variable, and outputting THAT instead on TMR0, in which case that
variable always outputs 0x00 since I initialize it in the beginning...

:( I don't get it, it should be super simple!

> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Tony Nixon
> Sent: Tuesday, August 28, 2001 8:42 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [PIC]: 16F870 TimerX Problems
>
>
> Nick Veys wrote:
> >
> > Been trying to get a timer to fire off on my 16F870 for a
> while now...
> >
> > I tried TMR0 since I had experience setting it on from my 16F84a.
> > Here are the steps I take:
> >
> > Set up TMR0 configuration stuff, prescalar, etc. (watchdog
> disabled of
> > course)
> > Enable T0 interrupt
> > Enable Global Interrupts
>
> This should work...
>
>         org 0h              ; startup vector = 0000
>
>         goto Start
>
>         org 4h
>
>         ; save registers etc.
>         bcf INTCON,T0IF
>         ; do something
>         ; restore registers
>         retfie
>
> ;
> ; ----------
> ; CODE START
> ; ----------
> ;
> Start   ; port setups etc.
>
>
>         bsf STATUS,RP0
>         movlw b'10000000'
>         movwf OPTION_REG   ; prescale = 1:2 = TMR0 = INT
>         bcf STATUS,RP0     ; ram page 0
>         clrf PCLATH
>
>
>         clrf TMR0
>         clrf INTCON
>         bsf INTCON,T0IE
>         bsf INTCON,GIE
> here    nop                ; jumps to IRQ on TMR0 overflow
>         goto here
>
>
>
>
>
> --
> Best regards
>
> Tony
>
> mICros
> http://www.bubblesoftonline.com mailto:sales@bubblesoftonline.com
>
> --
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>
>

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