Profibus Master Unit; Profibus Master Unit Features - Omron SYSMAC CS Series Operation Manual

PROFIBUS Master Unit

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PROFIBUS Master Unit

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PROFIBUS Master Unit Features

PROFIBUS Master Unit
CPU Bus Unit
Unit Control and Status
I/O Data
FINS Messages
PROFIBUS DP Class 1
Services
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The PROFIBUS Master Unit is a CPU Bus Unit, which can be installed on a
CS1/CJ1 PLC System. There are two available models of the PROFIBUS
Master Unit: the CS1W-PRM21 for connection to a CS1 PLC System and the
CJ1W-PRM21 for connection to a CJ1 PLC System. Both models provide
identical functionality.
A total of up to 16 CPU Bus Units can be mounted on the CPU Rack or an
Expansion Rack. The total of 16 must include all PROFIBUS Master Units and
all other CPU Bus Units
Up to 25 words of control and status words are exchanged between the
PROFIBUS Master Unit and a dedicated CIO memory area, of which the loca-
tion is related to the Unit Number. Control bits, allow the PLC program to
switch the Unit between OFFLINE, STOP, CLEAR and OPERATE mode,
which represent the main PROFIBUS DP modes of operation. The control
words also allow for user initiated transmission of a Global-Control message
over the PROFIBUS network to any group of slave devices.
The remaining CIO words provide status and diagnostics information on the
Unit itself, the PROFIBUS network and the slave devices.
The total size of I/O data however, must not exceed the maximum I/O size of
up to 7168 words, which it can exchange with the PLC memory. The I/O data
can be distributed over up to two input areas and two output areas. Each of
the input and output areas can be mapped to any location in the DM Area,
CIO Area, WR Area, HR Area, or the EM banks.
The PROFIBUS Master Unit supports FINS message exchange with the PLC
CPU to allow the transfer of Slave diagnostics data, the Error log, or to enable
or disable communication with specific allocated slave devices, so that they
can temporarily be taken out of the network for maintenance, without the
PROFIBUS Master Unit reporting an error.
As of Unit version 2.0, FINS commands have been implemented to support
the transfer of data via acyclic PROFIBUS messages over the network. These
messages can be used to change a slave device address, read slave device
configuration, or to send and receive extended parameter data information.
As of Unit version 3.0, a FINS command containing CIP data can be sent to
other OMRON devices on the PROFIBUS network, using PROFIBUS DP-V1
Class 2 services. CIP or Common Industrial Protocol is protocol defined by
ODVA, the Open Devicenet Vendor Association. Refer to their website for
more information: http://www.odva.org/.
The PROFIBUS Master Unit supports all mandatory Class 1 services defined
in the PROFIBUS DP standard EN50170, Volume 2 for Master - Slave Com-
munication. These functions includes the following services:
• Set_Prm
• Chk_Cfg
• Slave_Diag
• Data_Exchange
• Global-Control (FREEZE, UNFREEZE, SYNC, UNSYNC, CLEAR)
The PROFIBUS Master Unit supports cyclic Master - Slave communications
for networks with up to 125 slave devices. With each slave device it can
exchange up to 244 bytes of input data and up to 244 bytes of output data.
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