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Introduction
Section 3-1
3-1
Introduction
This section discusses the operational aspects of using the PROFIBUS-DP
Gateway to Host Link/Compoway-F Unit and the configuration software. The
section has been setup, to follow the general process flow of setting up and
configuring a network, downloading the configuration, and operating the
PROFIBUS network, the Compoway-F network or the Host Link network.
The PROFIBUS master can communicate with the Gateway with fixed com-
munication block and with free communication blocks.
In case Error messages are displayed, while using CX-Profibus, refer to the
appropriate manual for more information on errors.
Note
The maximum number of devices is 15.
The maximum of modules is 18. This number consists of 15 fixed communica-
tion blocks, 1 write, 1 read and 1 operation free communication block.
3-2
PROFIBUS communication
As mentioned in the previous chapter there are two ways of PROFIBUS com-
munication. Communication with fixed communication blocks and free com-
munication blocks.
Fixed communication
blocks
Fixed communication blocks are pre-defined blocks of data to be read/written
from/to a device. Fixed communication blocks are not adjustable. The most
common data can be read/written by using fixed communication blocks.
Free communication
blocks
Free communication blocks are sent directly to the slave device of the Gate-
way. The Gateway does not interfere with the data. With free communication
blocks it is possible to read/ write data which is not possible to read/write with
fixed communication blocks.
The maximum amount of PROFIBUS data the PRT1-SCU11 Gateway can
handle is 200 bytes input data and 200 bytes output data. If more capacity is
needed an extra slave device is required.
The I/O data words are sent in Big Endian format, i.e. the high byte is sent
first.