Omron SYSMAC CJ1W-PRM21, Руководство по эксплуатации

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9
PROFIBUS-DP Master Unit
Section 1-3
The GSD files are prepared individually by the vendor for each type of device,
according to a fixed format. Some parameters are mandatory, some have a
default value and some are optional. The device data base file is divided into
three parts:
General section
•
General specifications
This section contains the vendor name, the device name, hardware- and soft-
ware release versions, station type and identification number, protocol specifi-
cation and supported baud rates.
DP-master section
•
DP master-related specifications
This section contains all parameters which only apply to DP master devices
(e.g. maximum memory size for the master parameter set, maximum number
of entries in the list of active stations, or the maximum number of slaves the
master can handle).
DP-slave section
•
DP slave-related specifications
This section contains all specification related to slaves (e.g. minimum time
between two slave poll cycles, specification of the inputs and outputs, and
consistency of the I/O data).
DTM versus GSD file When comparing the two configuration technologies, a GSD file only provides
information on the device characteristics and configuration options. It has no
GUI of its own, nor can it connect to the device itself. A GSD file always
requires a separate configurator program to interpret the data. In the FDT/
DTM concept all these device related functions are included in the DTM. The
DTM can be executed from any program, which provides FDT interfaces.
1-3 PROFIBUS-DP Master Unit
1-3-1 PROFIBUS-DP Master Unit Features
PROFIBUS-DP Master Unit The PROFIBUS-DP 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-
DP 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.
CPU Bus Unit 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-DP Master units
and all other CPU Bus Units
Unit Control and status Up to 25 words of control and status words are exchanged between the
PROFIBUS-DP Master Unit and a dedicated CIO memory area, of which the
location is related to the Unit Number. Control bits, allow the PLC program to
switch the Unit between OFF-LINE, 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 stations.
The remaining CIO words provide status and diagnostics information on the
Unit itself, the PROFIBUS network and the Slave stations allocated to the
PROFIBUS-DP Master unit.
I/O data 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