I've added 'modedefs.bas' and set mode '0' still no joy

Code:
 CMCON0 = %00000111 
ANSEL = %00000000 
TRISIO = %00000000 
GPIO = %00000000
 
DEFINE SER2_BITS 8

INCLUDE "modedefs.bas"

MYVAR  VAR BYTE 
 
MAIN

pause250

serin2 GPIO.0, 0, [DEC MYVAR]

IF MYVAR = 3 THEN HIGH GPIO.5
PAUSE 250
GOTO MAIN