Standard Mode; Transparent Mode - W&T Electronics RS232 Handbuch

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Standard mode

In this mode switching between both data sources is
automatic on a time basis: the data sender that wants to
send something first uses a handshake stop signal or XOFF
character generated by the T-switch to automatically block
sending from the other source. If the first data sender inserts
a pause, then the second input is again ready to receive
after a settable switching time. The multi-computer adapter
automatically controls the data flow in this mode using the
handshake procedure set on the respective port.

Transparent mode

The data sender that wants to send something first is
immediately connected to the serial terminal device. All data
received on the other input of the T-switch are rejected as
long as the terminal device is connected to the first data
sender. Two conditions must be met in order to enable the
second input:
- The first data source has sent no more data since a
settable switching time.
- No more data have been received on the second input
since a likewise configurable timeout time.
This mechanism prevents the input from being activated in
the middle of a protocol block and thereby a fragmented
data record from reaching the receiver.
In this mode the Universal Serial T-Switch supports only the
two data lines RxD and TxD. The T-switch does not interfere
in the data flow in this mode, but rather transparently
passes the received data from the sender to the respective
receiver. The terminal devices themselves must provide for
any required control of the data flow.
Subject to error and alteration
RS232 Universal Serial T-Switch
35