Siemens SINAUT ST7 System Manual page 209

Connecting an MD2 with a TIM over the RS-232 port
Only one (1) MD2 modem can be connected to a TIM over the RS-232 port. This allows the
following end point and tapping point configurations.
Figure 5-15
Station control system
System Manual, 07/2009, C79000-G8976-C178-07
Connecting an MD2 to a TIM over RS-232, 2-wire and 4-wire end point variants
Installing and putting a SINAUT modem into operation
5.5 MD2 dedicated line modem
209