BayTech Telplex TX102, Руководство пользователя

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4.6.1 4.6.1 HARDWARE HANDSHAKING HARDWARE HANDSHAKING
4.6.1.1 4.6.1.1 CTS OUTPUT FLOW CONTROL CTS OUTPUT FLOW CONTROL
When information is received by a Telplex terminal port, the data is
stored in a receive buffer and is subsequently transmitted to the remote
unit through the composite port. If the receive buffer fills, the local Telplex
will make the terminal port's CTS line false (negative voltage), signaling
that it cannot receive more data. When the buffer empties to the point
where the port can accept more data, the local Telplex will make the
terminal port's CTS line true (positive voltage), signaling that it can
accept more data.
The local Telplex will also make the CTS line false for a terminal port if
the transmit buffer of the designated remote terminal port fills.
4.6.1.2 4.6.1.2 DTR INPUT FLOW CONTROL DTR INPUT FLOW CONTROL
When the Telplex transmits data out of a terminal port, the unit will expect
to see a false (negative voltage) on the DTR line if the terminal device is
unable to accept data. When the terminal device is ready to accept
data, the Telplex will expect to see a true (positive voltage) on the DTR
line.
If the DTR line is false on a local terminal port, the transmit buffer for that
port will begin to fill. If the transmit buffer fills, the local unit will signal the
remote unit to make the CTS line false on the designated remote
terminal port.
If XON/XOFF handshaking is enabled in the transmit data direction, the
Telplex will still check the state of the DTR line when transmitting data out
of a particular terminal port. By leaving the DTR line disconnected, the
DTR line is always enabled.