; 06-04-2008 ; Practica 3.ASM ; Apertura y cierre de cortinas ; PIC 16f84a ; MPLAB 8.00 ; PROTEUS 7.2 SP2 ; Guido Carmona Girón ;--------------- Encabezado ------------------------------------------------------- LIST P=16F84A, ; usar PIC 16F84A #include errorlevel -302 ;Eliminar banco mensajes __CONFIG _CP_OFF&_PWRTE_ON&_WDT_OFF&_XT_OSC ; code protec off ; power up timer on ; watchdog off ; osc: 1 MHz XT ;------------------------------------------------------------------------------------ CBLOCK 0x10 ; Temporary storage pos dc1 dc2 ENDC CBLOCK 0x10 ; Temporary storage ENDC ORG 0 entrypoint goto start ORG 4 intvector goto intvector start clrw ; Zero. movwf PORTB ; Ensure PORTB is zero before we enable it. bsf STATUS,RP0 ; Select Bank 1 movlw 0xF0 ; Set port B bits 0-3 as outputs movwf TRISB ; Set TRISB register. bcf STATUS,RP0 ; Select Bank 0 movlw 3 ; Initialize the motor position movwf pos movwf PORTB call delay clrf PORTB ; Motor drive off ;Main loop loop btfss PORTA,0 ; Test clockwise button call stepcw btfss PORTA,1 ; Test anti-clockwise button call stepccw goto loop ;Rotate one step clockwise stepcw bcf STATUS,C ; Clear the carry flag btfsc pos,3 ; Set carry if this bit set bsf STATUS,C rlf pos,W ; Pick up and rotate the motor's current position andlw 0x0F ; Mask to lower nibble movwf pos movwf PORTB ; Drive the outputs call delay ; Wait clrf PORTB ; Clear the output return ;Rotate one step counter clockwise stepccw bcf STATUS,C ; Clear the carry flag btfsc pos,0 bsf pos,4 rrf pos,W ; Pick up and rotate the motor's current position andlw 0x0F ; Mask to lower nibble movwf pos movwf PORTB ; Drive the outputs call delay ; Wait clrf PORTB ; Clear the output return ; This routine implements the delay between steps, ; and thus controls the motor speed. delay movlw 18 ; Outer loop iteration count movwf dc1 dl1 clrf dc2 ; Initialize inner loop dl2 nop nop decfsz dc2,F goto dl2 decfsz dc1,F goto dl1 return END