USART PIC18F45K20接收数据中断问题

时间:2014-04-12 13:40:08

标签: serial-port microchip pic18 usart

我目前正在为我的微电子类设计ARV,需要在PIC18f45k20上实现USART。到目前为止,我已经得到它在高优先级中断接收RCREG的第一个字符。但是,当它退出中断服务程序并且程序返回其主循环时,USART不会再次中断,也不会收到其他字符。我怀疑它与我的中断有关,因为它似乎收到了正确的数据。有关此问题的任何帮助吗?以下是我的代码。

    LIST        P=PIC18F45K20       ; list directive to define processor
    #INCLUDE    "P18F45K20.INC"     ; processor specific variable definitions

; CONFIG1H
  CONFIG  FOSC = INTIO67         ; Oscillator Selection bits (External RC oscillator, port function on RA6)
  CONFIG  FCMEN = OFF           ; Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)
  CONFIG  IESO = OFF            ; Internal/External Oscillator Switchover bit (Oscillator Switchover mode disabled)

; CONFIG2L
  CONFIG  PWRT = OFF            ; Power-up Timer Enable bit (PWRT disabled)
  CONFIG  BOREN = OFF       ; Brown-out Reset Enable bits (Brown-out Reset enabled in hardware only (SBOREN is disabled))
  CONFIG  BORV = 18             ; Brown Out Reset Voltage bits (VBOR set to 1.8 V nominal)

; CONFIG2H
  CONFIG  WDTEN = OFF           ; Watchdog Timer Enable bit (WDT is controlled by SWDTEN bit of the WDTCON register)
  CONFIG  WDTPS = 1         ; Watchdog Timer Postscale Select bits (1:32768)

; CONFIG3H
  CONFIG  CCP2MX = PORTC        ; CCP2 MUX bit (CCP2 input/output is multiplexed with RC1)
  CONFIG  PBADEN = ON           ; PORTB A/D Enable bit (PORTB<4:0> pins are configured as analog input channels on Reset)
  CONFIG  LPT1OSC = OFF         ; Low-Power Timer1 Oscillator Enable bit (Timer1 configured for higher power operation)
  CONFIG  HFOFST = ON           ; HFINTOSC Fast Start-up (HFINTOSC starts clocking the CPU without waiting for the oscillator to stablize.)
  CONFIG  MCLRE = ON            ; MCLR Pin Enable bit (MCLR pin enabled; RE3 input pin disabled)

; CONFIG4L
  CONFIG  STVREN = OFF           ; Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
  CONFIG  LVP = OFF              ; Single-Supply ICSP Enable bit (Single-Supply ICSP enabled)
  CONFIG  XINST = OFF           ; Extended Instruction Set Enable bit (Instruction set extension and Indexed Addressing mode disabled (Legacy mode))

 ; CONFIG5L
  CONFIG  CP0 = OFF             ; Code Protection Block 0 (Block 0 (000800-001FFFh) not code-protected)
   CONFIG  CP1 = OFF             ; Code Protection Block 1 (Block 1 (002000-003FFFh) not code-protected)
  CONFIG  CP2 = OFF             ; Code Protection Block 2 (Block 2 (004000-005FFFh) not code-protected)
  CONFIG  CP3 = OFF             ; Code Protection Block 3 (Block 3 (006000-007FFFh) not code-protected)

 ; CONFIG5H
  CONFIG  CPB = OFF             ; Boot Block Code Protection bit (Boot block (000000-0007FFh) not code-protected)
  CONFIG  CPD = OFF             ; Data EEPROM Code Protection bit (Data EEPROM not code-protected)

; CONFIG6L
   CONFIG  WRT0 = OFF            ; Write Protection Block 0 (Block 0 (000800-001FFFh) not write-protected)
  CONFIG  WRT1 = OFF            ; Write Protection Block 1 (Block 1 (002000-003FFFh) not write-protected)
  CONFIG  WRT2 = OFF            ; Write Protection Block 2 (Block 2 (004000-005FFFh) not write-protected)
  CONFIG  WRT3 = OFF            ; Write Protection Block 3 (Block 3 (006000-007FFFh) not write-protected)

 ; CONFIG6H
  CONFIG  WRTC = OFF            ; Configuration Register Write Protection bit (Configuration registers (300000-3000FFh) not write-protected)
   CONFIG  WRTB = OFF            ; Boot Block Write Protection bit (Boot Block (000000-0007FFh) not write-protected)
  CONFIG  WRTD = OFF            ; Data EEPROM Write Protection bit (Data EEPROM not write-protected)

 ; CONFIG7L
   CONFIG  EBTR0 = OFF           ; Table Read Protection Block 0 (Block 0 (000800-001FFFh) not protected from table reads executed in other blocks)
  CONFIG  EBTR1 = OFF           ; Table Read Protection Block 1 (Block 1 (002000-003FFFh) not protected from table reads executed in other blocks)
  CONFIG  EBTR2 = OFF           ; Table Read Protection Block 2 (Block 2 (004000-005FFFh) not protected from table reads executed in other blocks)
   CONFIG  EBTR3 = OFF           ; Table Read Protection Block 3 (Block 3 (006000-007FFFh) not protected from table reads executed in other blocks)

; CONFIG7H
  CONFIG  EBTRB = OFF           ; Boot Block Table Read Protection bit (Boot Block (000000-0007FFh) not protected from table reads executed in other blocks)



CBLOCK 0x60 ; allocation of memory for variable block
letters
letter1
letter2
letter3
letter4
letter5
letter6
letter7
letter8
letter9
letter10
txDelay1
txDelay2
input
saved
team_mem_block
data_to_write
working_data_add
progstate

ENDC

org 0h
goto setup  ;Start space in memory block
org 8h
goto HPISR  ;Start space for high priority interrupt
org 18h
goto LPISR  ;Start space for low priority interrupt

setup
     BSF     OSCCON,6
     BCF     OSCCON,5
     BSF     OSCCON,4
     CLRF    letters
     CLRF    letter1
    CLRF    letter2
    CLRF    letter3
    CLRF    letter4
    CLRF    letter5
    CLRF    letter6
    CLRF    letter7
    CLRF    letter8
    CLRF    letter9
    CLRF    letter10
    CLRF    txDelay1
    CLRF    txDelay2
    CLRF    saved
    CLRF    input
    CLRF    team_mem_block
    CLRF    data_to_write
    CLRF    working_data_add
    CLRF    progstate
    CLRF    PORTD
    CLRF    LATD
    CLRF    TRISD
    CLRF    INTCON  ; initialize interupt console

    ;----------------------------USART------------------------------------
    ;The configuration of the USART Bits for serial communication
    BSF     IPR1,RCIP
    BSF     IPR1,TXIP
    BCF     TXSTA,SYNC ; Asynchronous operation
    BSF     TXSTA,BRGH
    BSF     RCSTA,SPEN ; Enables the serial port and sets the TX/RX ports as input/output
    BSF     RCSTA,CREN
    BCF     BAUDCON,BRG16   ; 8-bit baudcon bit rate
    BCF     BAUDCON,DTRXP
    bsf     BAUDCON,CKTXP
    BSF     TXSTA,TXEN ; Enabling the transmitter
    bcf     RCSTA,RX9               ;8bits

    MOVLW   d'12'
    MOVWF   SPBRG
    BCF     TRISC,6 ; Set TX as output
    BSF     TRISC,7 ; Set RX as input
    CLRF    PORTC

    ;Eusart interupt bits
    BSF     PIE1,RCIE
    BCF     PIR1,RCIF
    BSF     INTCON,GIE
    BSF     INTCON,PEIE

    BSF     RCON, IPEN ; enable interupts
    BSF     INTCON, GIEH ; Enabling high and low priority interrupts
    BSF     INTCON, GIEL


start
    nop
    nop
    nop
    nop
    goto start

HPISR ;High Priority Interrupt Service Routine
    BCF     INTCON,GIE
   ; BSF     PORTD,0
    BSF     RCSTA,SPEN
   ; call    Transmit
   ; call    Transmit
   ; call    Transmit
   ; call    Transmit
   ; call    Transmit
   ; call    Transmit
   ; BCF     PORTD,0
     BTFSC   PIR1,RCIF
     goto    USART
     BSF     INTCON,GIE
     BCF     PIR1,RCIF
    retfie
 USART
    clrf    saved
    movff   RCREG,input
    movlw   0x0D
     cpfseq  input
    goto    save_letter_now
;       call    check
    goto    save_letter_end

 save_letter_now
     call save           ;save variable in correct location
save_letter_end
    BSF     PIE1,RCIE
    retfie

 save                    ; saving inputs into variables.
    bsf saved, 0
    incf letters
    movlw 0x01
    cpfsgt letters
    goto save_let1
    movlw 0x02
    cpfsgt letters
    goto save_let2
    movlw 0x03
    cpfsgt letters
    goto save_let3
    movlw 0x04
    cpfsgt letters
    goto save_let4
    btfss progstate, 0
    goto overflow
    movlw 0x05
    cpfsgt letters
    goto save_let5
    movlw 0x06
    cpfsgt letters
    goto save_let6
    movlw 0x07
    cpfsgt letters
    goto save_let7
    movlw 0x08
    cpfsgt letters
    goto save_let8
    movlw 0x09
    cpfsgt letters
    goto save_let9
    movlw 0x0A
    cpfsgt letters
    goto save_let10

 ; saving in different variables.
 save_let1
    movff input, letter1
    goto overflow
 save_let2
    movff input, letter2
    goto overflow
save_let3
    movff input, letter3
    goto overflow
save_let4
    movff input, letter4
    goto overflow
save_let5
    movff input, letter5
    goto overflow
save_let6
    movff input, letter6
    goto overflow
save_let7
    movff input, letter7
    goto overflow
save_let8
    movff input, letter8
    goto overflow
save_let9
    movff input, letter9
    goto overflow
save_let10
    movff input, letter10

overflow
    return

LPISR

    retfie

Transmit
    movlw   0xff
    movwf   txDelay1
TRANS_DELAY
    movlw   0x02
    movwf   txDelay2
TRANS_DELAY1
    decfsz  txDelay2, f
    goto    TRANS_DELAY1
    decfsz  txDelay1, f
    goto    TRANS_DELAY 
    return


        END

0 个答案:

没有答案