Siemens SIMATIC S7 - Page 467

Communication
8.6 RS485
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
467
Table 8- 22 Using Freeport mode
Network configuration
Description
Using Freeport over an
RS232 connection
Example: Using an S7-200 SMART CPU with an
electronic scale that has an RS232 port.
• Connect the two devices using one of the follow-
ing methods:
– RS232/PPI Multi-Master cable connects the
RS232 port on the scale to the RS485 port
on the CPU. (Set the cable to PPI/Freeport
mode, switch 5 = 0.)
– Using the CM01 signal board (SB) (S CPUs
only) which supports RS232 and RS485, you
can connect the RS232 device directly to the
CPU SB RS232 without using the RS232/PPI
cable.
• CPU uses Freeport to communicate with the
scale.
• Baud rate can be from 1.200 Kbps to
115.2 Kbps.
• User program defines the protocol.
Using USS protocol
Example: Using an S7-200 SMART CPU with
SIMODRIVE MicroMaster drives.
• STEP 7-Micro/WIN SMART provides a USS
library.
• The CPU is a master, and the drives are slaves.
Creating a user program
that emulates a slave
device on another net-
work
Example: Connecting S7-200 SMART CPUs to a
Modbus network.
• User program in the CPU emulates a Modbus
slave.
• STEP 7-Micro/WIN SMART provides a Modbus
library.