I am trying to use 18F1220 TMR0 as a timer. I have a momentary switch to ground on RB0, and I am looking with a scope for RB4 to go high when the timer overflows. I never see RB4 go high, even if I hold the switch down for a long period of time. Below is my code. Any help would be appreciated. (Compiles fine using MPASM). RB6 supplies power to the LCD.

TRISA = %00100000
TRISB = %00000111
WDTCON = 0
ADCON0 = 0
ADCON1 = %01111111
LVDCON = 0
CCP1CON = 0
OSCCON = %01101110

HIGH PORTB.6

DEFINE LCD_DREG PORTA
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 3
DEFINE LCD_BITS 4
DEFINE LCD_LINES 2
DEFINE LCD_COMMANDUS 2000
DEFINE LCD_DATAUS 50

TMR0ON VAR T0CON.7
T08BIT VAR T0CON.6
T0CS VAR T0CON.5
T0SE VAR T0CON.4
T0PSA VAR T0CON.3
T0PS2 VAR T0CON.2
T0PS1 VAR T0CON.1
T0PS0 VAR T0CON.0

GIE VAR INTCON.7
PEIE VAR INTCON.6
TMR0IE VAR INTCON.5
INT0IE VAR INTCON.4
RBIE VAR INTCON.3
TMR0IF VAR INTCON.2
INT0IF VAR INTCON.1
RBIF VAR INTCON.0

Main:

LCDOUT $fe,1
LCDOUT $fe,$C0

TMR0ON = 0
TMR0IF = 0

T08BIT = 0
T0CS = 0
T0PSA = 0
T0PS2 = 1
T0PS1 = 1
T0PS0 = 1
GIE = 1


IF PORTB.0 = 0 THEN GOTO Runtimer

GOTO Main

Runtimer:

TMR0ON = 1
TMR0IF = 0

IF TMR0IF = 1 THEN HIGH PORTB.4

GOTO Main

Thank you-
Dave