Specifications

Setting Up Communications Hardware and Network Communications
7-25
S7-200 Programmable Controller System Manual
C79000-G7076-C233-01
Using an 11-Bit Modem to Connect an S7-200 CPU to a STEP 7-Micro/WIN 32
Master
Using STEP 7-Micro/WIN 32 on a PC with a Windows 95, Windows 98, or
Windows NT operating system, or on a SIMATIC programming device (such as a
PG 740) as a single-master device, you can connect to one or more S7-200 CPUs.
Most modems are not capable of supporting the 11-bit protocol.
Depending on whether you want to connect to only one S7-200 CPU or to a
network of them (see Figure 7-19), you need the following:
 A standard RS-232 cable to connect the PC or SIMATIC programming device to
a full-duplex,11-bit local modem
 One of the following PC/PPI cables:
– A 5-switch PC/PPI cable (set to the proper baud rate, the 11- bit data
communications mode, and the DTE mode) to connect the remote modem
to the CPU
– A 4-switch PC/PPI cable (set to the proper baud rate) and a null modem
adapter to connect the remote modem to the CPU
 If there are multiple CPUs connected to the remote modem, you will need a
Siemens programming port connector on a PROFIBUS network (see
Figure 7-23 for the bias and termination of interconnecting cables).
11-bit
modem
RS-232
RS-232
COMx
RS-232
11-bit
modem
Telephone line
PG/
PC
CPU 224
4-Switch
PC/PPI cable
Null modem
adapter
Local
Remote
Full-duplex
Full-duplex
Note: x = your port number
25-pin to 9-pin
Adapter
Figure 7-19 S7-200 Data Communications Using an 11-Bit Modem with a 4-Switch PC/PPI
Cable