Baud Rate And Network Address; Definition Of Baud Rate And Network Address - Siemens Simatic S7 Series System Manual

Communication
8.6 RS485
PPI protocol and S7-200 SMART CPUs
PPI Advanced allows network devices to establish a logical connection between the devices.
With PPI Advanced, there are a limited number of connections supplied by each device. See
the following table for the number of connections supported by the S7-200 SMART CPU.
All S7-200 SMART CPUs support both PPI and PPI Advanced protocols.
Table 8- 13
Module
RS485 port
RS485/RS232 signal board
8.6.2

Baud rate and network address

8.6.2.1

Definition of baud rate and network address

Baud rate
The speed that data is transmitted across the network is the baud rate, which is typically
measured in units of kilobaud (kbaud) or megabaud (Mbaud). The baud rate measures how
much data can be transmitted within a given amount of time. For example, a baud rate of
19.2 kbaud describes a transmission rate of 19,200 bits per second.
Every device that communicates over a given network must be configured to transmit data at
the same baud rate. Therefore, the fastest baud rate for the network is determined by the
slowest device connected to the network.
The following table lists the baud rates supported by the S7-200 SMART CPU.
Table 8- 14
Network
PPI protocol
Freeport Mode
396
Number of connections for the S7-200 SMART CPU
Baud rate
9.6 kbaud, 19.2 kbaud, or 187.5 kbaud
9.6 kbaud, 19.2 kbaud, or 187.5 kbaud
Baud rate supported by the S7-200 SMART CPU
Connections
4
4
Baud rate
9.6 kbaud, 19.2 kbaud, and 187.5 kbaud only
1200 baud to 115.2 kbaud
System Manual, 09/2015, A5E03822230-AC
S7-200 SMART