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RS422 & RS485 Operation
RS422 is a four wire interface and supports full duplex (both transmit and receive active at the same time)
communications.
RS485 is a two wire interface and therefore supports
the Trve and Rve signals toge
thereby create the two wire interface required to connect to
RS485 requires one device on the network to be the master and
Remember that by connecting the Transmit and Receive differential pairs together (as above) then when you
transmit you will effectively place the transmit data into your receive buffer! So you need to ensure that you
discard this data before you look for data in your receive buffer.
RS422 RS485
Connector – P5 – GPIO
HB5 Touch Computer
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interface and supports full duplex (both transmit and receive active at the same time)
RS485 is a two wire interface and therefore supports half duplex operation. Therefore you need to connect
the Trve and Rve signals together and the Transmit –ve and Receive –ve signals together
required to connect to RS485 devices.
one device on the network to be the master and to set the protocol.
Transmit and Receive differential pairs together (as above) then when you
transmit you will effectively place the transmit data into your receive buffer! So you need to ensure that you
before you look for data in your receive buffer.
RS422 RS485
Touch Computer
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interface and supports full duplex (both transmit and receive active at the same time)
you need to connect
ve signals together to
Transmit and Receive differential pairs together (as above) then when you
transmit you will effectively place the transmit data into your receive buffer! So you need to ensure that you
