Siemens SIMATIC NET SINAUT ST7 System Manual page 244

Installing and putting a SINAUT modem into operation
6.4 MD2 dedicated line modem
Setting on
DIL switch
244
Meaning
Transmit level 0 dB / -9 dB
For more detailed information, refer to the description of the 10-
pin DIL switch at switch 10.
This allows the distance to be increased without regeneration.
4-wire mode
This setting is necessary if a separate wire pair is used for the
transmit and for the receive direction. In this mode, the setting
of switch 3 is irrelevant.
2-wire mode
This setting is necessary if a common wire pair is used for the
transmit and receive direction. In this mode, the setting of
switch 3 is relevant. This is then used to set whether only one 2-
wire line is actually connected (channel 1) or whether two 2-wire
lines are connected (channel 1+2), for example, in a control
center when communication to the stations is over two separate
2-wire connections ('small star network').
Channel 1 (2-wire)
In 2-wire mode, only channel 1 is used; in other words, only one
2-wire line is connected to the modem (see also switch 2).
Channel 1+2 (2-wire)
In 2-wire mode, channels 1+2 are used; in other words, two
separate 2- wire lines are connected to the modem (see also
switch 2).
Baud rate 1200 bps (see also note)
At this speed, the modem is compatible with SINAUT ST1
modems MD100, MD124 and LGM 1200H1.
Baud rate 2400 bps (see also note)
At this speed, the modem is compatible with the SINAUT ST1
MD124 modem.
Baud rate 9600 bps
Baud rate 19200 bps
At this speed, the modem is compatible with the SINAUT ST1
MD124 modem.
SINAUT ST7 Station control system - System Manual
System Manual, 05/2007, C79000-G8976-C178-06