I am trying to read the temperature from a DS1620 and send this to a PC
using the serial port, I know the serial portion of the code works I have
already tested that. I am having trouble reading from the DS1620 and I
wondered if anyone had any ideas on what I am doing wrong. Thanks.

;*******************************************************************
;Temperature
;*******************************************************************

        LIST P=16F628, R=DEC    ; Use the PIC16F628 and decimal system

        #include "P16F628.INC"  ; Include header file

        __config  _INTRC_OSC_NOCLKOUT & _LVP_OFF & _WDT_OFF & _PWRTE_ON &
_BODEN_ON

        CBLOCK 0x20             ; Declare variable addresses starting at
0x20
          dataL
          tempw
          count
          Delay_i
          Long_Delay_i
          tmp
        ENDC

        #define  DQ     PORTB, 4
        #define  CLK    PORTB, 5
        #define  RST    PORTB, 6

        ORG    0x000            ; Program starts at 0x000
;
; --------------------------------
; SET ANALOG/DIGITAL INPUTS PORT A
; --------------------------------
;
        movlw   0x07
        movwf   CMCON             ; CMCON=7 set comperators off
;
; ----------------
; INITIALIZE PORTS
; ----------------
;
        movlw   0x0                     ; 00000000
        movwf   PORTA

        movlw   0x4                     ; 00000100
        movwf   PORTB

        bsf     STATUS,RP0          ; RAM PAGE 1

        movlw   0xFF
        movwf   TRISA             ; 11111111

        movlw   0x12                        ; 00010010
        movwf   TRISB

; ------------------------------------
; SET BAUD RATE TO COMMUNICATE WITH PC
; ------------------------------------
; Boot Baud Rate = 9600, No Parity, 1 Stop Bit
;
        movlw   0x19              ; 0x19=9600 bps (0x0C=19200 bps)
        movwf   SPBRG
        movlw   0x24              ; brgh = high (2)
        movwf   TXSTA             ; enable Async Transmission, set brgh

        bcf     STATUS,RP0          ; RAM PAGE 0

        movlw   0x90                    ; enable Async Reception
        movwf   RCSTA
;
; ------------------------------------
; PROVIDE A SETTLING TIME FOR START UP
; ------------------------------------
;
        bcf             RST
        clrf    dataL
settle  decfsz  dataL,F
        goto    settle

        movf    RCREG,W
        movf    RCREG,W
        movf    RCREG,W            ; flush receive buffer
;
; ---------
; MAIN LOOP
; ---------
;
loop
                call    receive            ; wait for a char

                bsf     RST
                call    Delay
                movlw   0x0C
                call    sendDS

                movlw   0x03
                call    sendDS

                movlw   0xEE
                call    sendDS
                call    Delay

                movlw   0xAA
                call    sendDS
                call    Delay
                call    receiveDS
                bcf             RST
                call    send
                movlw   0x0D
                call    send
                movlw   0x0A
                call    send


                goto    loop

;
; -------------------------------------------
; RECEIVE CHARACTER FROM RS232 AND STORE IN W
; -------------------------------------------
; This routine does not return until a character is received.
;
receive btfss   PIR1,RCIF         ; (5) check for received data
        goto    receive

        movf    RCREG,W            ; save received data in W
        return
;
; -------------------------------------------------------------
; SEND CHARACTER IN W VIA RS232 AND WAIT UNTIL FINISHED SENDING
; -------------------------------------------------------------
;
send    movwf   TXREG             ; send data in W

TransWt bsf     STATUS,RP0          ; RAM PAGE 1
WtHere  btfss   TXSTA,TRMT        ; (1) transmission is complete if hi
        goto    WtHere

        bcf     STATUS,RP0          ; RAM PAGE 0
        return
;
; --------------
; SEND TO DS1620
; --------------
;
sendDS
                movwf   tempw
                movlw   8
                movwf   count
                bsf             STATUS,RP0      ;register page 1
            bcf         DQ      ; Set data for output.
            bcf         STATUS,RP0      ;register page 0

sendloop
                bcf     CLK
                btfsc   tempw, 0
              bsf       DQ
            btfss       tempw, 0
              bcf       DQ
            rrf         tempw, f
            bsf         CLK
                decfsz  count
                  goto  sendloop
                return

;
; -------------------
; RECEIVE FROM DS1620
; -------------------
;
receiveDS
                movlw   8
                movwf   count
                bsf             STATUS,RP0      ;register page 1
            bsf         DQ      ; Set data for input.
            bcf         STATUS,RP0      ;register page 0
receiveloop
                bcf     CLK
                rlf     tempw
                btfsc   DQ
                  bsf   tempw, 0
                btfss   DQ
                  bcf   tempw, 0
                bsf             CLK
                decfsz  count
                  goto  receiveloop
                movf    tempw, w
                return

Delay
        movlw 0xff
        movwf Delay_i
L1     nop
        decfsz Delay_i, f
        goto L1
        return

Long_Delay
        movwf tmp
        movlw 0xff
        movwf Long_Delay_i
L2     call Delay
        decfsz Long_Delay_i, f
        goto L2
        movf tmp,w
        return

        END



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