Communication
8.5 PROFIBUS
8.5.1.2
Using the EM DP01 to connect an S7-200 SMART as a DP device
You can connect the S7-200 SMART CPU to a PROFIBUS DP network through the
EM DP01 PROFIBUS DP module. You connect the EM DP01 to the S7-200 SMART CPU as
an expansion module, and you connect the PROFIBUS network to the EM DP01
PROFIBUS DP module through its DP communications port. This port operates at any
PROFIBUS baud rate between 9.6 Kbps and 12 Mbps. Refer to the
EM DP01 PROFIBUS DP module Technical Specifications for the baud rates supported.
Note
The CPU models CPU CR20s, CPU CR30s, CPU CR40s, and CPU CR60s do not support
the use of expansion modules or signal boards.
As a PROFIBUS DP device, the EM DP01 accepts several different I/O configurations from
the DP master, allowing you to tailor the amount of data transferred to meet the
requirements of the application. Unlike many DP devices, the EM DP01 does not transfer
only I/O data. The EM DP01 also transfers inputs, counter values, timer values, or any other
values that you move to the variable memory in the S7-200 SMART CPU. Likewise, the
EM DP01 transfers data from the DP master to the variable memory in the S7-200 SMART
CPU. You can then move this data from variable memory to other data areas.
You can attach the DP port of the EM DP01 PROFIBUS DP module to a DP master on the
network and still communicate as an MPI device with other master devices such as SIMATIC
HMI devices or S7-300 / S7-400 CPUs on the same network. The following figure shows a
PROFIBUS network with an S7-200 SMART CPU SR20 and an EM DP01 PROFIBUS DP
module:
● The S7-300 with CPU 315-2 is the DP master and has been configured by a SIMATIC
programming device with STEP 7 programming software. The S7-315-2 DP can read
data from or write data to the EM DP01, from 1 byte up to 244 bytes.
● The S7-200 SMART CPU SR20 is a DP device owned by the CPU 315-2. The ET 200 I/O
module is also a DP device owned by the CPU 315-2.
● The S7-400 CPU is attached to the PROFIBUS network and is reading data from the
CPU SR20 by means of X_GET instructions in the S7-400 CPU user program. (Other
SIMATIC CPUs can use DB1 to access V memory in the S7-200 SMART CPU.)
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System Manual, V2.3, 07/2017, A5E03822230-AF
S7-200 SMART