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settng up rs232 variable

phil Jones

Hi, can anyone tell me how i would set up a variable that expects a certain amount of data to be received through rs232.

i.e. to receive 18 bytes of data only once the the rx pin has been set to input.

thanks guys

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    this can not be answewred - at least by me- based on the scant information youn give.
    1) you do not state which derivative you use, the below is based on 'plain vanilla' derivatives
    2) WHY
    3) the Rx pin should ALWAYS "be set to input" (there IS NO SUCH THING as setting a pin to input for the '51, the pins are ALWAYS quasi-bidirectional) if you write a zero to p0.1 you will burn either the RS232 transceiver or the '51 or both.
    4) seems like a simple counter till you disable RE; reset IES; stop whatever timer run the UART; ....

    Erik

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  • 0

    this can not be answewred - at least by me- based on the scant information youn give.
    1) you do not state which derivative you use, the below is based on 'plain vanilla' derivatives
    2) WHY
    3) the Rx pin should ALWAYS "be set to input" (there IS NO SUCH THING as setting a pin to input for the '51, the pins are ALWAYS quasi-bidirectional) if you write a zero to p0.1 you will burn either the RS232 transceiver or the '51 or both.
    4) seems like a simple counter till you disable RE; reset IES; stop whatever timer run the UART; ....

    Erik

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