User`s manual

Hardware automatically enables the
transmitters when transmitting.
Transmitters will turn off three
bit-times after the last stop bit of the
last character, regardless of baud
rate. Used in two-wire
communication.
Auto Toggle
DTR is set to enable the transmitters.
Used in two-wire communication
Half Duplex using DTR
RTS is set to enable the transmitters.
Used in two-wire communication.
Half Duplex using RTS
Transmitters and receivers are
always enabled; ports can send and
receive simultaneously. Used in
four-wire communication.
Full Duplex
RS-422/485 Duplex Mode
Receivers are only enabled when not
transmitting. In a Half Duplex
mode, you will not receive what you
transmit.
When NOT Tranmitting
Receivers are always enabled. In a
Half Duplex mode, you will receive
what you transmit (sometimes
called echo).
Always Receive
Receive Control
RTS routed to CTS, AUXIN routed
to RCLK, and TCLK routed to
AUXOUT. Used to connect ports
transmitting at different baud rates.
In order to function, all ports must
have and use this feature.
Clocks
RTS routed to AUXOUT, AUXIN
routed to CTS, and TCLK routed to
RCLK. Used when RTS/CTS
handshaking is required.
Modem Control
RTS routed to CTS, AUXIN routed
to AUXOUT, and TCLK routed to
RCLK. Used when external
handshaking or clocking signals are
not available.
Loopback All
RS-422/485 Connector Setup
4-11 DSP-200/300 (Rev. I and later) User's Manual
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