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Dallas 1-Wire Issue (DS18B20)

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Can someone see what I'm doing wrong here.
It is in relation to checking if the sensor is busy doing a temp conversion...
Resolution is 12 bit so it should take 750mS
How do I properly check the sensors busy status?

I structured it like this so I can put this in the main loop and execute other tasks while the conversion is taking place. Didn't want to use interrupt for this. Open to suggestions on a better way to do this also....
Code:
MAIN_LOOP  

GET_TEMP
  ; Check FLAG, 4 to determin if temp sensors finished Temperature Conversion and ready for next conversion
        BTFSC   FLAGS, 4 
        GOTO    CONVERSION_NOT_READY
  ; Broadcast temperature conversion command to 1-Wire bus
        CALL    OW_RESET                ; Reset
        MOVLW   H'CC'                   ; Skiprom (send to all devices)
        CALL    OW_WRITE_BYTE           ; 
        MOVLW   H'44'                   ; Convert T
        CALL    OW_WRITE_BYTE           ; 
       
        BSF     FLAGS, 4                ; Set to indicate temp sensors busy
CONVERSION_NOT_READY


       

TEMPERATURE_CONVERSION_DONE?
        CALL    OW_READ_BIT             ; Initiate Read Time Slots
        BTFSS   STATUS, C               ; DS18B20 transmits a 0 while the temperature conversion is in progress and a 1 when the conversion is done
        GOTO    CONVERSION_NOT_DONE     ; Transmitting 0 therefore NOT done
       
        CALL    OW_RESET                ; Reset
        MOVLW   H'CC'                   ; Skiprom
        CALL    OW_WRITE_BYTE           ; 
        MOVLW   H'BE'                   ; Read Scratchpad
        CALL    OW_WRITE_BYTE           ; 
       
        CALL    OW_READ_BYTE            ; Move Scrachpad Byte 0 to W
        MOVWF   TEMP_C_L                ; Store in Celsius TEMPLO GPR
        CALL    OW_READ_BYTE            ; Move Scrachpad Byte 1 to W
        MOVWF   TEMP_C_H                ; Store in Celsius TEMPHI GPR
  ; Clear flag to indicate temp sensors ready for next conversion
        BCF     FLAGS, 4                ; Temp sensors ready for another Convert T Command
CONVERSION_NOT_DONE

  ; ... rest of main loop here...
The 1-Wire Subroutines. (Which im confident are fine because they work if I change the main code.
Code:
  ; Dallas 'One Wire' Communication Routines. 
  ; DISABLE INTERRUPTS DURING TIME CRITICAL COMMUNICATION
OW_RESET  ; This routine Resets devices on the 1-Wire bus
        CALL    DQ_LL                   ; Force the DQ Line to Logic Low
        MOVLW   (D'500'-5)/5            ; Reset pulse must be held a minimum of 480uS. 
        CALL    DELAY                   ; For delays from 10uS to 1285uS. Example, MOVLW D'10' for 10uS, MOVLW D'500' for 500uS. (D'n'-5)/5; n must be divisable by 5
        CALL    DQ_HIZ                  ; Release DQ Line
        MOVLW   (D'70'-5)/5             ; Wait for recovery
        CALL    DELAY                   ; 
        BTFSC   PORTB, 0                ; Test for 'Presence Pulse'
        GOTO    OW_RESET                ; If not present, Reset
        MOVLW   (D'430'-5)/5            ; Must wait a minmum of 480uS from when DQ line is released before moving on
        CALL    DELAY                   ; 
        RETURN                          ;
       
OW_READ_BYTE  ; This routine reads a byte of data from the DS18B20
        MOVLW   H'08'                   ; Amount of bits to shift out
        MOVWF   COUNT                   ; Store in COUNT GPR
        CALL    OW_READ_BIT             ; Read bit
        RRF     SHIFT, F                ; Rotate bit out of carry into SHIFT GPR
        DECFSZ  COUNT, F                ; Decrement COUNT
        GOTO    $-D'3'                  ; If not zero, read next bit
        MOVF    SHIFT, W                ; If zero, move SHIFT GPR to W
        RETURN                          ;
       
OW_READ_BIT  ; This routine reads one bit of data from the DS18B20
        BCF     INTCON, GIE             ; Disable Global Interrupts
        CALL    DQ_LL                   ; Force the DQ Line to Logic Low
        CALL    DQ_HIZ                  ; Release DQ Line
        BSF     STATUS, C               ; Preset Carry Flag
        BTFSS   PORTB, 0                ; Test DQ Line
        BCF     STATUS, C               ; If zero, Clear Carry Flag
        BSF     INTCON, GIE             ; Enable Global Interrupts
        MOVLW   (D'60'-5)/5             ; Wait for Time Slot to end
        CALL    DELAY                   ; 
        RETURN                          ;
       
OW_WRITE_BYTE  ; This routine writes a byte of data to the DS18B20
        MOVWF   SHIFT                   ; Move data to shift into DS18B20 to SHIFT GPR
        MOVLW   D'08'                   ; Amount of bits to shift in
        MOVWF   COUNT                   ; Store in COUNT GPR
        RRF     SHIFT, F                ; Rotate valid data into Carry Flag
        CALL    OW_WRITE_BIT            ; Write bit
        DECFSZ  COUNT, F                ; Decrement COUNT
        GOTO    $-D'3'                  ; If not zero, read next bit
        RETURN                          ; If zero, RETURN
       
OW_WRITE_BIT  ; This routine writes one bit of data to the DS18B20
        BCF     INTCON, GIE             ; Disable Global Interrupts
        CALL    DQ_LL                   ; Force the DQ Line to Logic Low
        BTFSS   STATUS, C               ; Test Carry Flag
        GOTO    $+D'2'                  ; If zero, leave DQ Line Logic Low
        CALL    DQ_HIZ                  ; If not zero, release DQ Line to Logic High
        MOVLW   (D'60'-5)/5             ; Hold Logic Low, write 0
        CALL    DELAY                   ; 
        CALL    DQ_HIZ                  ; If not zero, release DQ Line to Logic High, write 1
        BSF     INTCON, GIE             ; Enable Global Interrupts
        RETURN                          ; 
       
DQ_HIZ  ; This routine forces the DQ Line to an Input / High Impedance state
        BSF     STATUS, RP0             ; Bank 1
        BSF     TRISB, 0                ; Make Pin 3 an input, Pullup resistor forces line to logic 1, unless DS18B20 pulls it low
        BCF     STATUS, RP0             ; Bank 0
        RETURN
       
DQ_LL  ; This routine forces the DQ Line to Logic Low
        BCF     PORTB, 0                ; Clear output latch
        BSF     STATUS, RP0             ; Bank 1
        BCF     TRISB, 0                ; Make Pin 3 an output
        BCF     STATUS, RP0             ; Bank 0
        RETURN
       
DELAY  ; This routine can provide delays from 10uS to 1285uS depending on the number moved to the Working register prior to calling the delay
        MOVWF   DELAYGPR1               ; Move integer to GPR
        NOP                             ; No Operation
        NOP                             ; No Operation
        DECFSZ  DELAYGPR1, F            ; Decrement GPR and place back in itself
        GOTO    $-D'3'                  ; Not finished, GOTO here - 3 instructions
        RETURN                          ; Finished, Return
 
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