PIC microcontroller two-machine synchronous communication design

"Single chip microcomputer dual computer synchronous communication 1. MCU pic1 programming (master control sending) LIST P=16F876 #INCLUDE P16F876.INC CBLOCK 0X24 ； Three bytes are reserved for display COUNT ； Used as a counter or register ENDC ORG 0X0000 ； Program reset entry NOP START GOTO MAIN ORG 0X0100 MAIN MOVLW 0X30 MOVWF FSR ； The RAM contents starting from 30h unit will be initialized below MOVLW 0X30 ； Assign the value 30h to the unit 30h MOVWF COUNT INTRAM MOVF COUNT，0 ； Assign 30h ~ 7FH to units 30h ~ 7FH MOVWF INDF INCF COUNT，1 INCF FSR，1 BTFSS COUNT，7 GOTO INTRAM BSF STATUS，RP0 ； Initialize SCI part MOVLW 0X19 ； Set the baud rate for transmission to approximately 9600 bps MOVWF SPBRG MOVLW 0X94 ； Select synchronous high-speed mode to transmit 8-bit data MOVWF TXSTA BCF STATUS，RP0 MOVLW 0X80 ； Allow synchronous serial port operation MOVWF RCSTA BSF STATUS，RP0 BSF TRISC，7 ； Set RC6 and RC7 as input mode and disconnect from external circuit BSF TRISC，6 BSF STATUS，RP0 MOVLW 0X30 ； Transfer the content from 30h unit to pic2 MOVWF FSR MOVF INDF，0 MOVWF TXREG ； Write the data to be transmitted to the transmission buffer txreg BSF STATUS，RP0 BSF TXSTA，TXEN ； Send allow BCF STATUS，RP0 TX1 BTFSS PIR1，TXIF ； Wait until the last data is written GOTO TX1 INCF FSR ； Ready to send next data MOVF INDF，0 MOVWF TXREG ； Write new data to txreg BTFSS FSR，7 ； Judge whether the contents of all 30h ~ 7FH units have been sent? GOTO TX1 ； If not, continue to send other bytes TX2 BTFSS PIR1，TXIF ； Wait until all the data required to be sent has been sent, and then add additional data GOTO TX2 ； Write a byte to txreg so that the last data can be sent smoothly MOVWF TXREG NOP ； After a delay of several microseconds, turn off the transmission permission NOP NOP NOP NOP BSF STATUS，RP0 BCF TXSTA，TXEN BCF STATUS，RP0 CALL LED ； Call the display subroutine to display the sent data END ； Program finished 2. MCU pic2 programming (slave receiving) LIST P=16F876 #INCLUDE P16F876.INC CBLOCK 0X24 COUNT ENDC ORG 0X0000 NOP START GOTO MAIN ORG 0X0100 MAIN BSF STATUS，RP0 MOVLW 0X10 ； Select synchronous driven mode MOVWF TXSTA BCF STATUS，RP0 MOVLW 0X80 ； Serial port enable MOVWF RCSTA BSF STATUS，RP0 BSF TRISC，7 ； Turn off the connection with the external circuit BSF TRISC，6 BCF STATUS，RP0 MOVLW 0X30 ； Store the received data from the 30h unit MOVWF FSR BSF RCSTA，CREN ； Receiving permission WAIT BTFSS PIR1，RCIF ； Waiting to receive GOTO WAIT MOVF RCREG，0 ； Read received data MOVWF INDF ； Store the received data into the ram of pic2 INCF FSR BTFSS FSR，7 ； Have all data been received? GOTO WAIT ； No, continue to receive other bytes NOP ； After a delay of several microseconds, clear the receive permission bit NOP NOP NOP BCF RCSTA，RCEN CALL LED ； Call the display subroutine to display the received data END ； After the program, read the full text“