Point-To-Point Operation-Multiplexer And Terminal With Dial-Up Feature Installed - IBM 2740-1 System Reference Manual

runs out of paper (paper presence contact not locked
out).
The (c ) signal switches the terminal to standby
status (Standby light on, keyboard remains locked,
except for the Bid and EOT keys, and the terminal
motor is turned off).
If the terminal is in local mode (or is in commu­
nicate mode but without Status) when the (S ) signal
is received, an alarm sounds at the terminal.
operator may now switch to the communicate mode
(by positioning the Local/Communicate switch to
Com) or insert paper. Message reception from the
multiplexer is not possible until this is accompli­
shed.
Point-to-Point Operation—Multiplexer and Terminal
with Dial-Up Feature Installed
The dial-up operation of a terminal and multiplexer
is essentially the same as a point-to-point terminal
and multiplexer operation without the dial-up fea­
ture installed. When the dial-up feature is used,
a communication line connection must be established
before the terminal and multiplexer can communi­
cate with each other (Figures 8 and 9). The
terminal must be in a standby status before attempting
to make a line connection.
Transmit
Before transmitting from the terminal to the multi­
plexer, a communication line connection must be
established in the following manner.
press Talk button on data set, and dial the multi­
plexer. The data set at the multiplexer should be
equipped with the auto-answer feature.
places a high-pitched tone on the line when the
multiplexer is called (provided the Auto button on
Terminal A
SWITCHED
NETWORK
Terminal B or
Connect
Multiplexor
Figure 8. Dial-Up Operation (Dial-Up Adapter Special Feature)
The
Lift receiver,
This feature
D
I
A
Bid Key
EOT Key
L
®
B
Text
O
V
V
V
the multiplexer data set has been operated pre­
viously), which indicates that a line connection has
been established.
P ress Data button on terminal data set and place
receiver in cradle. The Dial-Connect light will be
on indicating the line is connected and the terminal
is in a standby status. From this point on, the
operation of the terminal is the same as a term inal-
to-multiplexer operation without the dial-up feature
(see " Point-to-Point Operation—Multiplexer and
Terminal" in this section of manual and Figures
5 and 6). While the terminal is in a receive or
transmit status the Dial-Connect light is off, even
though the line is still connected.
on again when the terminal switches to a standby
status.
At the completion of transmission, the line must
be disconnected as follows.
key; this disconnects the line at both the terminal
and the multiplexer, provided both data sets have
the automatic disconnect feature installed. Auto
disconnect is available as a terminal special feature
on IBM World Trade machines.
Receive
To receive from the multiplexer, the terminal must
be in a standby status with the Auto button on the
data set pressed down. The auto-call capability
of the multiplexer data set (special feature) enables
the multiplexer to call the terminal automatically.
The Auto button on the data set (having previously
been operated) enables the terminal to answer the
incoming call automatically, establish a line con­
nection, and turn the Dial-Connect light on. Once
the line connection is established, the multiplexer
transmits a ^5) signal, which switches the terminal
to a receive status.
Bid Key EOT Key
© Text O
Y
©
Bid
Key
©
from
Mult
Principles of Operation, Model 1
The light turns
P ress Dial-Disconnect
Dial Disc Key
A
Y
Text © Disconnect
EOT
Key
from
Mult
15