PIC 12F683 and DS18B20 problem

Hi everyone,

I'm trying to obtain the temperature using four DS18B20s and transfer the result to my PC using serial port. My code is below, but I couldn't obtain the result I wanted, when I simulated using Proteus. I used SEROUT command instead of HSEROUT, because this PIC model doesn't have built in USART. Maybe I did a mistake using this command. I'd be glad, if you can help. (BTW i'm using MicroCode studio and MPASM).

Code :

'************************************************* ***************
'* Name : UNTITLED.BAS *
'* Author : [select VIEW...EDITOR OPTIONS] *
'* Notice : Copyright (c) 2012 [select VIEW...EDITOR OPTIONS] *
'* : All Rights Reserved *
'* Date : 27.02.2012 *
'* Version : 1.0 *
'* Notes : *
'* : *
'************************************************* ***************
@ __CONFIG _WDT_OFF & _MCLRE_ON & _CP_OFF & _PWRTE_ON & _CPD_OFF & _BOD_OFF & _FCMEN_ON & _IESO_OFF & _INTRC_OSC_NOCLKOUT

OSCCON = %01100001
DEFINE XTAL = 4

PortA=0

Busy VAR BIT
HAM VAR WORD
HEAT VAR WORD
FLOAT VAR WORD
SIGN_BIT VAR HAM.Bit11
NEG_HEAT CON 1
DEGREE CON 223
SIGN VAR BYTE
TEMP VAR BYTE
COMM_PIN VAR PORTA.0
COMM_PIN1 VAR PORTA.1
COMM_PIN2 VAR PORTA.2
COMM_PIN3 VAR PORTA.3
CLEAR

START:
GOSUB READSENSOR
GOSUB READSENSOR1
GOSUB READSENSOR2
GOSUB READSENSOR3
GOTO START

READSENSOR:
OWOUT Comm_Pin,1,[$CC,$44]

WAT :
OWIN COMM_PIN,4,[Busy]
IF Busy=0 THEN WAT
OWOUT COMM_PIN,1,[$CC,$BE]
OWIN COMM_PIN,2,[HAM.Lowbyte,ham.highbyte]
GOSUB CALC
RETURN

CALC:
SIGN = "+"
IF SIGN_BIT = NEG_HEAT THEN
SIGN = "-"
TEMP = ($FFFF - HAM + 1)*625
HEAT = DIV32 10
GOTO SUB
ENDIF
TEMP = 625*HAM
HEAT = DIV32 10

SUB:
FLOAT = (HEAT//1000)/100
HEAT = (HEAT/1000)

SEROUT PORTA.0,2,[HEAT,10]
RETURN

READSENSOR1:
OWOUT Comm_Pin1,1,[$CC,$44]

WAT1 :
OWIN COMM_PIN1,4,[Busy]
IF Busy=0 THEN WAT1
OWOUT COMM_PIN1,1,[$CC,$BE]
OWIN COMM_PIN1,2,[HAM.Lowbyte,ham.highbyte]
GOSUB CALC1
RETURN

CALC1:
SIGN = "+"
IF SIGN_BIT = NEG_HEAT THEN
SIGN = "-"
TEMP = ($FFFF - HAM + 1)*625
HEAT = DIV32 10
GOTO SUB1
ENDIF
TEMP = 625*HAM
HEAT = DIV32 10

SUB1:
FLOAT = (HEAT//1000)/100
HEAT = (HEAT/1000)

SEROUT PORTA.1,2,[hEAT,10]
RETURN

READSENSOR2:
OWOUT Comm_Pin2,1,[$CC,$44]

WAT2 :
OWIN COMM_PIN2,4,[Busy]
IF Busy=0 THEN WAT2
OWOUT COMM_PIN2,1,[$CC,$BE]
OWIN COMM_PIN2,2,[HAM.Lowbyte,ham.highbyte]
GOSUB CALC2
RETURN

CALC2:
SIGN = "+"
IF SIGN_BIT = NEG_HEAT THEN
SIGN = "-"
TEMP = ($FFFF - HAM + 1)*625
HEAT = DIV32 10
GOTO SUB2
ENDIF
TEMP = 625*HAM
HEAT = DIV32 10

SUB2:
FLOAT = (HEAT//1000)/100
HEAT = (HEAT/1000)

SEROUT PORTA.2,2,[HEAT,10]
RETURN

READSENSOR3:
OWOUT Comm_Pin3,1,[$CC,$44]

WAT3 :
OWIN COMM_PIN3,4,[Busy]
IF Busy=0 THEN WAT3
OWOUT COMM_PIN3,1,[$CC,$BE]
OWIN COMM_PIN3,2,[HAM.Lowbyte,ham.highbyte]
GOSUB CALC3
RETURN

CALC3:
SIGN = "+"
IF SIGN_BIT = NEG_HEAT THEN
SIGN = "-"
TEMP = ($FFFF - HAM + 1)*625
HEAT = DIV32 10
GOTO SUB3
ENDIF
TEMP = 625*HAM
HEAT = DIV32 10

SUB3:
FLOAT = (HEAT//1000)/100
HEAT = (HEAT/1000)

SEROUT PORTA.3,2,[HEAT,10]
RETURN
END