51 control MT8880 dual audio transceiver assembly program

        ORG 0000H

                        AJMP MAIN

                                :

                                :

;********************

;* 8880 Initialization *

;********************

MAIN: MOV A, #90H

                        MOV P0, A ; write 8880CRA

                        MOV P0, A ; write 8880CRA

                        MOV A, #98H

                        MOV P0, A ; write 8880CRA

                        MOV A, #90H

                        MOV P0, A ; write 8880CRB

                        MOV A, #94H

                        MOV P0, A ; write 8880CRA, 8880 mode 1 is DTMF, IRQ

                                :

                                :

;****************

;* Receiving program *

;****************

                        MOV R1, #0

                        MOV R0, #10H

LOOP1: MOV A, #0FFH

                   MOV P0, A

                        SETB P0.7

                        SETB P0.4

                        CLR P0.5

                        SETB P0.6

                        MOV A, P0 ; Read 8880 status register

                        JNB A CC .2, LOOP1

                        CLR P0.4

                        MOV A, P0 ; Read 8880 receive data register

                        ANL A, #0FH ; shield the upper four bits

                        MOV @R0, A

                        INC R0

                        INC R1

                        CJNE R1, #07H, LOOP1

                                :

                                :

;****************

;* Code issuing procedure *

;****************

                        MOV R0, #10H

                        MOV R1, #7

                        MOV A, #9DH ; Write 8880CRA

                        MOV P0, A

                        MOV A, #90H

                        MOV P0, A ; write 8880CRB, 8880 mode 2 is TONE, DTMF, IRQ, BURST

LOOP2: MOV A, @R0

                        ORL A, #0F0H

                        ANL A, #8FH

                         MOV P0, A ; send data

                        MOV A, #0FFH

                        MOV P0, A

                        SETB P0.7

                        SETB P0.4

                        CLR P0.5

                        SETB P0.6

LOOP3: MOV A, P0 ; Read 8880 status register

                        JNB ACC.1, LOOP3

                        INC R0

                        DJNZ R1, LOOP2

                                    :

                                    :

Note: The above program has not been debugged, please pay attention to the CS status. For information on MT8880, please refer to 

MT8880 transceiver program (8051 series)

Note:  P0.0-P0.3 of the MCU  are connected to D0-D3 of 8880 respectively; P0.4-P0.7 of the MCU are connected to RS0\ CS \R/ W \Ø2 of 8880 respectively. (Ø2 is controlled by the clock and P0.7)

                                ORG 0000H

                        AJMP MAIN

                                :

                                :

;********************

;* 8880 Initialization *

;********************

MAIN: MOV A, #90H

                        MOV P0, A ; write 8880CRA

                        MOV P0, A ; write 8880CRA

                        MOV A, #98H

                        MOV P0, A ; write 8880CRA

                        MOV A, #90H

                        MOV P0, A ; write 8880CRB

                        MOV A, #94H

                        MOV P0, A ; write 8880CRA, 8880 mode 1 is DTMF, IRQ

                                :

                                :

;****************

;* Receiving program *

;****************

                        MOV R1, #0

                        MOV R0, #10H

LOOP1: MOV A, #0FFH

                   MOV P0, A

                        SETB P0.7

                        SETB P0.4

                        CLR P0.5

                        SETB P0.6

                        MOV A, P0 ; Read 8880 status register

                        JNB ACC.2, LOOP1

                        CLR P0.4

                        MOV A, P0 ; Read 8880 receive data register

                        ANL A, #0FH ; shield the upper four bits

                        MOV @R0, A

                        INC R0

                        INC R1

                        CJNE R1, #07H, LOOP1

                                :

                                :

;****************

;* Code issuing procedure *

;****************

                        MOV R0, #10H

                        MOV R1, #7

                        MOV A, #9DH ; Write 8880CRA

                        MOV P0, A

                        MOV A, #90H

                        MOV P0, A ; write 8880CRB, 8880 mode 2 is TONE, DTMF, IRQ, BURST

LOOP2: MOV A, @R0

                        ORL A, #0F0H

                        ANL A, #8FH

                         MOV P0, A ; send data

                        MOV A, #0FFH

                        MOV P0, A

                        SETB P0.7

                        SETB P0.4

                        CLR P0.5

                        SETB P0.6

LOOP3: MOV A, P0 ; Read 8880 status register

                        JNB ACC.1, LOOP3

                        INC R0

                        DJNZ R1, LOOP2

                                    :

                                    :

Note: The above program has not been debugged, please pay attention to the CS status