SIEMENS
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Siemens IK PI · 2015
PROFIBUS
Communication for SIMATIC S7-300
CP 342-5
3
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Function
The CP 342-5 provides access to different communication
services of the PROFIBUS bus system:
• PROFIBUS DP
(according to IEC 61158/61784, master or slave)
•
PG/OP communication
•
S7 communication (client, server)
•
Open communication (SEND/RECEIVE)
PROFIBUS DP master
The CP 342-5 operates as a DP-V0 Master according to
IEC 61158/EN 61784 Volume 2 and processes the data transfer
completely independently. It supports the services of the
Master Classes 1 and 2.
The data areas of the distributed I/Os are transferred consis-
tently between CP and CPU. This applies to the use of the CP as
DP Master and as DP Slave. As DP Master, it permits connec-
tions to:
•
SIMATIC S7-300, such as CP 342-5 as DP slave
•
DP slaves of the distributed I/O system ET 200
(integrate as DP-V0 slave)
•
PCs, e.g. with CP 5512, CP 5621, CP 5614 A3 and
SOFTNET-PB DP
The CP 342-5 also offers the SYNC/FREEZE and shared input/
output functions, as well as the activation/deactivation of
DP slaves.
PROFIBUS DP slave
The CP 342-5 as a DP-V0 slave permits the SIMATIC S7-300 to
exchange data with other PROFIBUS DP masters. which allows
a hybrid setup between SIMATIC S5/S7, PCs, ET 200 and other
field devices to PROFIBUS DP. Function calls are required for
the DP communication. These (DP-SEND/DP-RECV) must be
integrated in the STEP 7 user program.
PG/OP communication
PG/OP communication allows all S7 stations connected to the
network to be remotely programmed.
•
S7 routing
With the aid of S7 routing it is possible to use programming
device communication across networks.
Via the CP 342-5 as many as 16 TD/OPs can be merged into
one S7-300 station. This requires only one connection
resource in the S7-CPU (multiplex channel). The multiplex
channel supports the acyclic HMI services.
S7 communication
S7 communication is used for the coupling:
•
between SIMATIC S7 automation systems
•
to HMI devices (OPs).
•
to PCs, e.g. CP 5711 with SOFTNET-PB S7, CP 5623 etc.
Communication with PG and OP takes place without further
configuration. In addition, the central controller can also be
programmed and configured on a distributed basis via the
CP 342-5.
The client functionality is provided by means of loadable
communication blocks.
Open communication (SEND/RECEIVE)
Based on Layer 2 (FDL) of PROFIBUS, the CP 342-5 offers a
simple, optimized interface for process or field communication.
This interface offers integrated, high-performance communica-
tion between SIMATIC S5, SIMATIC S7, SIMATIC 505 and PC.
SEND/RECEIVE provides not only the SDA service (PLC/PLC
connections) but also the SDN service (broadcast, multicast).
The communication partners are the automation systems:
•
SIMATIC S7
with CP 342-5, CP 343-5, CP 443-5 Extended and Basic
•
SIMATIC S5
with S5-95U with PROFIBUS interface, S5-115U/H, S5-135U,
S5-155U/H with CP 5431 FMS/DP
•
SIMATIC 505
with CP 5434-FMS
• PCs
with CP 5512, CP 5611 A2, CP 5621, CP 5613 A3,
CP 5613 FO, CP 5614 A3, CP 5623, CP 5624
•
Systems of other makes that are equipped with an
FDL interface.
To use SEND/RECEIVE, function calls are required (PLC-SEND/
PLC-RECEIVE), which must be linked into the STEP 7 user
program.
Diagnostics
Extensive diagnostic options are available via STEP 7, including:
•
Status of the CP
•
General diagnostics and statistics functions
•
Connection diagnostics
•
Bus statistics
•
Message buffer
STEP 7 V5.5 SP2 or higher, or STEP 7 Professional V11 or higher,
is required for configuring the full functional scope of the
CP 342-5. In Version V5 or higher of STEP 7, the configuration
data of the CP can also optionally be stored on the CPU and is
retained even if there is a power failure. A module can therefore
be replaced without having to reload the configuration data from
a programming device. The CPU transfers the configuration
data to the CP during start-up. Attention should therefore be
paid to the memory capacity of the S7-CPU.
Configuration and programming of all SIMATIC S7 controllers
connected to the network is possible over the network.
The function blocks for PROFIBUS DP are included in the
standard library of STEP 7. The function blocks for using the
open communication (SEND/RECEIVE) and S7 communication
(S7 client) can be found in the SIMATIC NET library following
installation of STEP 7.
© Siemens AG 2014