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how to program this code from DS18S20@DS1820 to LM 35..please help me..thank :)

chomix05

Feb 7, 2012
1
Joined
Feb 7, 2012
Messages
1
list p=16f628
#include <p16f628.inc>
errorlevel 0,-302

CBLOCK 0x20
DS_DAT
DS_SIGN
DUMMY0
DUMMY1
DUMMY2
DUMMY3
DUMMY4
SEND
COUNT
NUM1
NUM2
NUM3
DATA1
HALF
endc
#define DAT_PIN PORTB,0 ; 74595 DATA pin
#define LATCH PORTB,4 ; 74595 LATCH pin
#define CLK PORTB,5 ; 74595 CLK pin
#Define DQ PORTA,0

org 0x000
goto Start

Table_ addwf PCL,f
dt 0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f

Start clrf PORTA ; Set port A for digital I/O
movlw 0x07
movwf CMCON
bsf STATUS,RP0
movlw b'00000110' ; Set port B for displaying via LED 7 segments
movwf PORTB
bcf STATUS,RP0

Main call RD_Temp ; Read data from DS1820
clrf HALF ; A Half digit
bcf STATUS,C
rrf DS_DAT,w ; Use 7-bit upper
rlf HALF,f ; Store a half degree
movwf DATA1 ; Data for convert to decimal
call Convert ; Convert data to decimal
call Delay3 ; Display data delay
goto Main

;**********************************************************************
; Display On 7 Segment *
;**********************************************************************
Delay3 clrf DUMMY4 ; Display data delay
DelayLp call Disp
decfsz DUMMY4,f
goto DelayLp
return

Delay2 clrf DUMMY3 ; Delay for scanning LED 7 segments
decfsz DUMMY3,f
goto $-1
return

Disp movf NUM1,w ; Load data to DSP1
call Table_ ; Convert
btfsc HALF,0 ; Show a half degree on dot-point LED
addlw 0x80
call Send_Dat ; Send data to LED 7 segments
bcf PORTB,6 ; ON DSP1 Display
call Delay2
bsf PORTB,6
movf NUM2,w ; Load data to DSP2
call Table_ ; Convert
call Send_Dat ; Send data to LED 7 segments
bcf PORTB,7 ; On DSP2
call Delay2
bsf PORTB,7 ; Off DSP2
return

Send_Dat movwf SEND ; Load data
movlw 0x08 ; Loop 8 times for sending 8-bit data
movwf COUNT
Chk_Bit bcf DAT_PIN ;
btfsc SEND,7 ; Check bit 7 "0" or "1"
bsf DAT_PIN ; Send bit 7 to shift register
Clock bsf CLK ; Clock pulse
bcf CLK
Rotate rlf SEND,f ; Rotate bit for sending next bit
decfsz COUNT,f ; Test loop 8 times ?
goto Chk_Bit ; If no, send bit again
Latch bsf LATCH ; Latch data for displaying
bcf LATCH
return

;**********************************************************************
; Macro for DS1820 *
;**********************************************************************
DQLOW macro
bcf DQ ; DQ bit ready
bsf STATUS,RP0
bcf DQ ; Set DQ to output
bcf STATUS,RP0
endm

DQHIZ macro
bsf STATUS,RP0
bsf DQ ; Set DQ to input
bcf STATUS,RP0
endm

PAUSE macro DELAY ; Generate delay time
movlw DELAY
movwf DUMMY0
call Delay5
endm

;**********************************************************************
; DS1820 1-Wire bus *
;**********************************************************************
RD_Temp call DS_Rx ; Check chip status
addlw 0x01
btfss STATUS,Z ; Z set = ready
return ; W is not zero = not ready

Get_Temp call DS_Reset

movlw 0xcc ; Skip ROM
call DS_Tx

movlw 0xbe ; Read scratch pad RAM of DS1820
call DS_Tx
call DS_Rx ; Read 8-bit data
movwf DS_DAT

call DS_Reset ; Restart

movlw 0xcc ; Skip ROM
call DS_Tx

movlw 0x44 ; Start conversion
call DS_Tx

Delay5 nop ; Delay for PAUSE macro
nop
decfsz DUMMY0,f
goto Delay5
return

DS_Reset DQLOW
PAUSE 0x77 ; 600 microcsecond delay
DQHIZ
PAUSE 0x0c ; Wait for response pulse (67 microsecond)
nop
nop
movf PORTA,w ; Read response
andlw 0x01 ; Use RA0 only
movwf DUMMY1
PAUSE 0x3b ; 300 microcsecond delay
movf DUMMY1,w ; Response in W
return

DS_Tx movwf DUMMY2 ; Transmission data
movlw 0x08 ; Prepare 8-bit counter for sending data
movwf DUMMY1 ; Define loop counter
Tx_Loop DQLOW ; Macro of DQ pin to low, This is start bit
PAUSE 0x01 ; 10 microsecond delay
rrf DUMMY2,f ; Rotate data to Carry flag
btfsc STATUS,C ; Test Carry flag
bsf DQ ; If Carry flag = "1" , set DQ to high
PAUSE 0x0d ; 70 microsecond delay
DQHIZ
nop
decfsz DUMMY1,f ; 8 times ?
goto Tx_Loop ; No, send again
return

DS_Rx movlw 0x08 ; Recieve 8-bit data
movwf DUMMY1
Rx_Loop DQLOW ; Macro of DQ pin to low, this is start bit
PAUSE 0x01 ; 10 microsecond delay
DQHIZ ; Back to high for receiving
nop
nop
movf PORTA,w ; Read data
andlw 0x01 ; Get data bit 0 only
addlw 0xff ; Move data bit 0 to Carry flag with addition method
rrf DUMMY2,f ; Move data bit 0 to DUMMY bit 7
PAUSE 0x0b ; 60 microsecond delay
decfsz DUMMY1,f ; Loop 8 times
goto Rx_Loop ; Read again
movf DUMMY2,w ; Save data to W register
return

;**********************************************************************
; Convert Hex to Decimal (3 Digit) *
;**********************************************************************
Convert clrf NUM2 ; Clear register of 10's unit
Check movlw 0x0A ;
subwf DATA1,w ; Subtract with 10 until lower 10
btfss STATUS,C ; Check subtraction result lower 10 ?
goto Less1 ; If yes then return
incf NUM2,f ; If no, increase 10's unit value
movlw 0x0A ;
subwf DATA1,f ; Subtract with 10 until lower 10 and check result again
goto Check

Less1 movf DATA1,w ;
movwf NUM1 ; Send data to 1's unit display
clrf NUM3 ; Check hundred unit
Check2 movlw 0x0A
subwf NUM2,w ;
btfss STATUS,C ; 10's unit over 10 ?
return ; If no then return
incf NUM3,f
movlw 0x0A ; If yes, subtract again and check until the result is lower 10
subwf NUM2,f
goto Check2
;**********************************************************************
end
 

jackorocko

Apr 4, 2010
1,284
Joined
Apr 4, 2010
Messages
1,284
This is asm code for a
#include <p16f628.inc>
PIC16F628.
DS1820 is a digital thermometer.

What uC do you plan to port this code to? Each uC has slight differences and you will need to change the code to reflect this. It's not as easy as copy/paste upload to new uC. You also need the correct compiler this code was written for or you will not get it to compile correctly without porting the code as well.
 
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