simple problem...easy answer?

I am trying to connect my PC to an 8051 then connect that to another 8051 and then to another to a second PC..... so basically i want to send a character from one PC to another through the two boards.

I have two different files, one called transmit.a51 and one called receive.a51, transmit.a51 looks like:

Code:

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org        8100h

rxbuf:        jnb        RI, rxbuf        ;check for received byte from PC
        clr        RI                ;clear RI, ready for next character
        mov        A, SBUF                ;move character to acc from SBUF
        clr        p1.0                ;set p1.0 to logic 0
        acall        delay                ;call delay
        setb        p1.0                ;set p1.0 to logic 1

        clr        p3.4                ;change ports to AUX port

        clr        p1.7                ;set p1.7 to logic 0
        acall        delay                ;call delay
        setb        p1.7                ;set p1.7 to logic 1
        mov        SBUF, A                ;move charcter to SBUF from acc
txbuf:        jnb        TI, txbuf        ;send character and test for transmitted
        clr        TI                ;clear TI ready for next character
        sjmp        rxbuf                ;jumps back to start of program

delay:        mov        r3, #0ffh
loop1:        mov        r2, #0ffh
take:        djnz        r1,take
        djnz        r3,loop1
        ret

        END

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and receive.a51 like this:

Code:

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org        8100h

        clr        p3.4                ;change ports to AUX port
rxbuf:        jnb        RI, rxbuf        ;check for received byte from TAD 1
        clr        RI                ;clear RI, ready for next character
        mov        A, SBUF                ;move character to acc from SBUF
        clr        p1.7                ;set p1.7 to logic 0
        acall        delay                ;call delay
        setb        p1.7                ;set p1.7 to logic 1

        clr        p1.0                ;set p1.0 to logic 0
        acall        delay                ;call delay
        setb        p3.4                ;change ports to primary port
        setb        p1.0                ;set p1.0 to logic 1
        mov        SBUF, A                ;move charcter to SBUF from acc
txbuf:        jnb        TI, txbuf        ;send character and test for transmitted
        clr        TI                ;clear TI ready for next character
        sjmp        rxbuf                ;jumps back to start of program

delay:        mov        r3, #0ffh
loop1:        mov        r2, #0ffh
take:        djnz        r1,take
        djnz        r3,loop1
        ret

        END

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when i run them only one character is ent and then the program gets stuck. My problem is the program dosen't loop back to the start and when i try to setb p3.4 at the start of the program it freaks out!!

I think i need to loop the program to go back and check for another character after transmitting or receiving.....not sure though!!

can anyone help me please???