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1-5
Section
Functions of the DeviceNet (CompoBus/D) Interface Unit
10
The main functions of the Configurator are illustrated below. For details, refer to
the DeviceNet (CompoBus/D) Configurator Operation Manual (W328).
Configurator
functions
Setup functions
Setting remote I/O allocations (scan list)
Setting other Master parameters (initial remote
I/O status, communications cycle time)
Setting Slave parameters for Slaves not from
OMRON
Monitoring functions
Displaying connected device lists
Monitoring Master status, Master error histories,
and communications cycle times
Operating functions
Starting/stopping remote I/O communications
File management functions
Reading/writing files for connected device data
(online) and device data resulting from setting
Master parameters (offline)
Note
1. Connect only one Configurator to each Network.
2. Do not use a Configurator in locations subjected to excessive noise, particu-
larly when using a PCMCIA Card. Excessive noise will cause the computer
to run out of control. (This will not, however, adversely affect the DeviceNet
network.)
3. The OMRON Configurator can only be used for OMRON Master Units
(CVM1-DRM21-V1, C200HW-DRM21-V1). Do not use the Configurator for
other company’s Master Units.
1-5
Functions of the DeviceNet (CompoBus/D) Interface Unit
A PT connected to the DeviceNet Interface Unit uses the Memory Link method.
In the Memory Link method, the PT memory area within the PT is treated as a
virtual PC memory area. This method allows PT memory and PT display ele-
ments to be accessed with simulated direct access.
1-5-1 Communications Using the DeviceNet Interface Unit
With the regular Memory Link method, the PT and host are connected through
RS-232C or RS-422A communications and the host controls the PT through the
PT memory by sending commands to the PT that read/write PT memory data.
When a DeviceNet Interface Unit is used, the PT is connected to the host (Mas-
ter) through the DeviceNet network. In contrast to the regular Memory Link
method, PT memory is accessed using one of the following two methods.
The DeviceNet Interface Unit is connected to the network as a DeviceNet Slave.
As a DeviceNet Slave, the input and output areas can each contain up to 32
words.
In the DeviceNet system, the input area is regularly read by the Master and the
output area is regularly written from the Master. This process maintains consis-
tency between the Slave’s input and output areas and the input and output areas
allocated to the Master.
Once the PT memory’s input and output areas have been set, PT memory can
be read and written without having the host (Master) manage communications.
The maximum size of the input and output areas is only 32 words each, but data
is transferred automatically at high speed so it is useful to allocate areas that re-
quire regular data transfers with the host such as the PT status control area and
PT status notify area or areas that are frequently refreshed such as the numeral
memory tables.
Parts of PT memory other than the input and output areas can be read/written by
sending explicit messages from the host.
Main Configurator
Functions
Accessing PT Memory
through Input and Output
Areas
Accessing PT Memory
with Explicit Message
Communications