UART 3.2v Full to 5v Half Duplex Interface

Discussion in 'Embedded Systems and Microcontrollers' started by BillMerryman, Jan 7, 2016.

  1. BillMerryman

    Thread Starter New Member

    Jan 7, 2016
    Greetings All,

    I am trying to connect a 3.2 volt Full Duplex UART to a 5 volt Half Duplex device. The pins on the 3.2 volt device are not 5 volt tolerant (it is a Beaglebone Black). Would a device like this work: . It is an RS-485 transceiver breakout board. It appears it will address the full to half duplex conversion (I have additional pins from the BBB available to toggle between send and receive), I'm just not sure if it will protect the BBB from the 5V while it is receiving. I'm trying to avoid having to use an additional board for level conversion. Any help greatly appreciated.

  2. ScottWang


    Aug 23, 2012
    I think you should attach a block diagram to shows how your wiring and label the voltages.
  3. sailorjoe


    Jun 4, 2013
    I would consider starting with this logic level converter to protect my BBB, and then work on the transceiver problem as a separate issue.
    In general, going from full duplex to half duplex means that you basically give up on full duplex. If that's OK, then keep going.