Можете сравнить с этим (почти Ваш контроллера
) :
************************************************** *******
;THE experiment is to familiarity the use of DS18B20
;SIX LED display temperature,the integer is two digit,the decimal fraction is four digit.
;THE hardware request:the DS18B20 must insert in the 18B20 socket
; SW S10 the first bit ON,the other bit OFF
; SW S5ЎўS6 must set ON, the other SWS must set OFF.
;*****************THE definiens of register*****************************
#INCLUDE‹P16F877A.INC›
#DEFINE DQ PORTA,0 ;18B20 data port
__CONFIG _DEBUG_OFF&_CP_ALL&_WRT_HALF&_CPD_ON&_LVP_OFF&_BOD EN_OFF&_PWRTE_ON&_WDT_OFF&_HS_OSC
CBLOCK 20H
DQ_DELAY1
DQ_DELAY2
TEMP
TEMP1
TEMP2 ;keep the temperature of sampling
TEMP3
COUNT
COUNT1
ENDC
TMR0_VALUE EQU 0AH ;register initial value is 6,prescaler is 1Јє4,the time of one interrupt is 4*ЈЁ256-6Ј©=1000us
DQ_DELAY_VALUE1 EQU 0FAH
DQ_DELAY_VALUE2 EQU 4H
;**********************start of program************************
ORG 00H
NOP
GOTO MAIN ;the address of entrance
ORG 04H
RETFIE ;place a interrupt return instruction in the address of interrupt entrance
TABLE
ADDWF PCL,1
RETLW 0C0H ;the code of 0( the common LED is anode)
RETLW 0F9H ;the code of 1
RETLW 0A4H ;the code of 2
RETLW 0B0H ;the code of 3
RETLW 99H ;the code of 4
RETLW 92H ;the code of 5
RETLW 082H ;6
RETLW 0F8H ;7
RETLW 080H ;8
RETLW 090H ;9
;***************************main program*******************************
MAIN
CLRF PORTA
CLRF PORTB
BANKSEL TRISA
CLRF TRISA ;the A PORT SET OUTPUT
CLRF TRISD
MOVLW 01H
MOVWF TRISB ;set B0 PORT INPUT,the other OUTPUT
MOVLW 06H
MOVWF ADCON1 ;close all A/D PORT
MOVLW 01H
MOVWF OPTION_REG ;prescaler is 1Јє4,timer,inside clock
BCF STATUS,RP0
CLRF TEMP
CLRF TEMP1
CLRF TEMP2 ;clear all temporary register
MOVLW 8H
MOVWF COUNT
MOVLW 38H
MOVWF FSR
CLRF INDF
INCF FSR,1
DECFSZ COUNT,1
GOTO $-3
;****************************the cycle of program************************
;startup 18B20 temperature conversion program,judge if the conversion of temperature have finished(need 750us)
;if have not finished CALL display subprogram, till finish the conversion of temperature
;if finish the conversion of temperature read the temperature
;send to led display
LOOP
BTFSC PORTB,0 ;judge if the temperature convert key press
GOTO LOOP1 ;no ,jump to display
CALL DELAY ;remove shake
BTFSC PORTB,0 ;judge again
GOTO LOOP1
CALL RESET_18B20 ;CALL reset 18B20 subprogram
MOVLW 0CCH
MOVWF TEMP
CALL WRITE_18B20 ;SKIP ROM command
MOVLW 44H
MOVWF TEMP
CALL WRITE_18B20 ;temperature convert command
CLRF STATUS
CALL DELAY_750MS ;CALL 64 DISPLAY subprogram,ensure the time of transform temperature (need 750us)
NOP
CALL RESET_18B20
MOVLW 0CCH
MOVWF TEMP
CALL WRITE_18B20 ;SKIP ROM command
MOVLW 0BEH
MOVWF TEMP
CALL WRITE_18B20 ;READ temperature command
CALL READ_18B20 ;READ temperature low byte
MOVFW TEMP
MOVWF TEMP1 ;keep in TEMP1
CALL READ_18B20 ;READ temperature high byte
MOVFW TEMP
MOVWF TEMP2 ;keep in TEMP2
CALL RESET_18B20
LOOP1
CALL TEMP_CHANGE ;CALL temperature conversion subprogram
CALL DISPLAY ;CALL LED display
GOTO LOOP ;circle work
;*********************reset DS18B20 subprogram**************************
RESET_18B20
;DATASHEET introduce,write data must conform to next prescript:
;main controller pull low general line at least 480us,
;18B20 wait 15-60us, pull low general line as the responsion to the main controller
BANKSEL TRISA
BCF TRISA,0
BCF STATUS,RP0
BCF DQ
MOVLW 0A0H
MOVWF COUNT ;160US
DECFSZ COUNT,1
GOTO $-1 ;pull low 480us
BSF DQ ;release general line
MOVLW 14H
MOVWF COUNT
DECFSZ COUNT,1
GOTO $-1 ;wait 60us
BANKSEL TRISA
BSF TRISA,2 ;DQ set INPUT
BCF STATUS,RP0
BTFSC DQ ;IF the data line is low
GOTO RESET_18B20 ;otherwise continue reset
MOVLW 4H
MOVWF COUNT
DECFSZ COUNT,1 ;delay some time judge again
GOTO $-1
BTFSC DQ
GOTO RESET_18B20
MOVLW 4BH
MOVWF COUNT
DECFSZ COUNT,1
GOTO $-1
BANKSEL TRISA
BCF TRISA,0 ;DQ set OUTPUT
BCF STATUS,RP0
RETURN
;*********************write DS18B20 subprogram****************************
WRITE_18B20
;DATASHEET introduce,write data must conform to next prescript:
;write data 0,main controller pull low general line at least 60us
;write data 1,main controller pull low general line ,but must release in 15us
MOVLW 8H
MOVWF COUNT ;eight bit data
BANKSEL TRISA
BCF TRISA,0
BCF STATUS,RP0
BCF STATUS,C
WRITE_18B20_1
BSF DQ ;first keep DQ high
MOVLW 5H
MOVWF COUNT1
BCF DQ ;pull low DQ15us
DECFSZ COUNT1,1
GOTO $-1
RRF TEMP,1
BTFSS STATUS,C ;judge the write data is 0 or 1
GOTO WRITE_0
BSF DQ ;if is 1,pull high data line at once
GOTO WRITE_END
WRITE_0
BCF DQ ;continue keep data line low
WRITE_END
MOVLW 0FH
MOVWF COUNT1 ;keep 45us
DECFSZ COUNT1,1
GOTO $-1
BSF DQ ;release general line
DECFSZ COUNT,1 ;if finish 8 bit data
GOTO WRITE_18B20_1
RETURN
;**********************read DS18B20 subprogram****************************
READ_18B20
;DATASHEET introduce,write data must conform to next prescript:
;read data 0,main controller first pull low general line,18B20 pull low 60us again
;read data 1,after main controller pull low general line,keep general line state
; main controller after data line pull low inside 15us read the state of data line
MOVLW 8H ;read 8 bit data once
MOVWF COUNT
READ_18B20_1
BANKSEL TRISA
BCF TRISA,0 ;data line set OUTPUT
BCF STATUS,RP0
BCF DQ ;first pull low data line
MOVLW 1H
MOVWF COUNT1
DECFSZ COUNT1,1 ;pull low general line 3us
GOTO $-1
BSF DQ ;release general line
BANKSEL TRISA
BSF TRISA,0 ;data line set INPUT
BCF STATUS,RP0
MOVLW 2H
MOVWF COUNT1
DECFSZ COUNT1,1 ;delay 6us
GOTO $-1
BSF STATUS,C
BTFSS DQ ;judge the state of data line
BCF STATUS,C
RRF TEMP,1 ;shift to TEMP
MOVLW 12H
MOVWF COUNT1
DECFSZ COUNT1,1
GOTO $-1 ;read one bit data must require 60us
DECFSZ COUNT,1 ;if finish reading 8 bit
GOTO READ_18B20_1
RETURN
;*******************temperature format conversion subprogram**************************
;because the temperature read from 18B20 is binary,must change into ASCII display on LED
;18B20 temperature format is:S S S S S 2 of 6 power,2 of 5 power,2 of 4 power,2 of 3 power,
;2 of 2 power,2 of negative 4 power,
;the result integer keep in the start of 38H register,decimal fraction keep in the start of 3BH register
;38H(hundred bit)39H(ten bit)3AH(Entries bit)3BH(decimal dot)3CH(ten cent bit)3DH(hundred cent bit)
;3EH(thousand cent bit),3FH(myriad cent bit)
TEMP_CHANGE
;integer data
;because after change temperature the data is keep in two registers ,so must combine in one register
;because the max value is 127.9375,so judge the value if big that 100 to decide the result of hundred bit
;use circle sub 0AH receive the ten bit,the leave minuend is Entries bit
MOVLW 7H
ANDWF TEMP2,0 ;only keep 3 bit
MOVWF 3AH ;keep in 3AH
SWAPF 3AH,1
MOVFW TEMP1
MOVWF TEMP3 ;keep in TEMP2
MOVLW 0F0H
ANDWF TEMP3,1 ;clear low four bits
SWAPF TEMP3,0 ;swap high half byte and low half byte
IORWF 3AH,1 ;combine is result of 7 bit integer data
MOVLW 64H ;calculate hundred bit of integer data
SUBWF 3AH,W ; -100
BTFSS STATUS,C
GOTO NEXT0 ;temperature less than 100
MOVWF 3AH ;decrease result cover the old data
MOVLW 1H
MOVWF 38H ;integer MSB is 1(impossible big than 1)
GOTO $+2
NEXT0
CLRF 38H ;temperature less than 100,the MSB is 0
CLRF 39H ;calculate integer ten bit
MOVLW 0AH ; -10
SUBWF 3AH,1
BTFSS STATUS,C
GOTO NEXT1
INCF 39H,1 ;enough sub,ten bit add 1
GOTO $-5
NEXT1
MOVLW 0AH
ADDWF 3AH,1 ;reset the old data,the data is Entries bit
MOVLW '.'
MOVWF 3BH ;decimal dot
;decimal data
;get four bit precision
;the method of calculate is from the lowest bit judge the bit is 1,if is 1 add:
;0.0625Ўў0.125Ўў0.25Ўў0.5Ј¬ and only hundred cent bit add ,the result can big than 0AH
CLRF 3CH
CLRF 3DH
CLRF 3EH
CLRF 3FH
BTFSS TEMP1,0
GOTO NEXT2
MOVLW 5H
MOVWF 3FH
MOVLW 2H
MOVWF 3EH
MOVLW 6H
MOVWF 3DH ;myriad cent bit
NEXT2
BTFSS TEMP1,1
GOTO NEXT3
MOVLW 5H
ADDWF 3EH,1
MOVLW 2H
ADDWF 3DH,1
MOVLW 1H
MOVWF 3CH ;thousand cent bit
NEXT3
BTFSS TEMP1,2
GOTO NEXT5
MOVLW 5H
ADDWF 3DH,1
MOVLW 0AH
SUBWF 3DH,1
BTFSS STATUS,C
GOTO NEXT4
INCF 3CH,1
GOTO $+3
NEXT4
MOVLW 0AH
ADDWF 3DH,1
MOVLW 2H
ADDWF 3CH,1 ;hundred cent bit
NEXT5
BTFSS TEMP1,3
GOTO NEXT6
MOVLW 5H
ADDWF 3CH,1 ;ten cent bit
NEXT6
RETURN
;*******************************display subprogram*******************************
;entrance parameter:39H(ten bit)3AH(Entries+decimal dot)3CH(ten cent bit)
;3DH(hundred cent bit)3EHЈЁthousand cent bitЈ© 3FHЈЁmyriad cent bitЈ©
;exit parameter:no
DISPLAY
BANKSEL TRISA
CLRF TRISA ;A PORT ALL SET OUTPUT
CLRF STATUS
MOVFW 39H ;display temperature ten bit
CALL TABLE
MOVWF PORTD
BCF PORTA,0
CALL DELAY
BSF PORTA,0
MOVFW 3AH ;display temperature Entries bit
CALL TABLE
MOVWF PORTD
BCF PORTD,7 ;decimal dot
BCF PORTA,1
CALL DELAY
BSF PORTA,1
MOVFW 3CH ;display temperature ten cent bit
CALL TABLE
MOVWF PORTD
BCF PORTA,2
CALL DELAY
BSF PORTA,2
MOVFW 3DH ;display temperature hundred cent bit
CALL TABLE
MOVWF PORTD
BCF PORTA,3
CALL DELAY
BSF PORTA,3
MOVFW 3EH ;display temperature thousand cent bit
CALL TABLE
MOVWF PORTD
BCF PORTA,4
CALL DELAY
BSF PORTA,4
MOVFW 3FH ;display temperature myriad cent bit
CALL TABLE
MOVWF PORTD
BCF PORTA,5
CALL DELAY
BSF PORTA,5
RETURN
;***************************delay subprogram************************************
DELAY
GOTO $+1
GOTO $+1
GOTO $+1
GOTO $+1
GOTO $+1
GOTO $+1
RETURN
;**************************delay 750ms******************************
DELAY_750MS
MOVLW DQ_DELAY_VALUE2
MOVWF DQ_DELAY2
DELAY_750MS_2
MOVLW DQ_DELAY_VALUE1
MOVWF DQ_DELAY1
DELAY_750MS_1
MOVLW TMR0_VALUE
MOVWF TMR0 ;start timer
BTFSS INTCON,T0IF
GOTO $-1
BCF INTCON,T0IF
DECFSZ DQ_DELAY1,1
GOTO DELAY_750MS_1
DECFSZ DQ_DELAY2,1
GOTO DELAY_750MS_2
RETURN
;**************************program end******************************
END
Проблема с DS18B20 + PIC, HELP!
