Omron K3HB, Техническое руководство пользователя

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10-2
Detailed DeviceNet Specifications
Section 8-1
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8-1 Detailed DeviceNet Specifications
Data Size and Connection Types
If the connection type can be set when another company’s configurator is being used, select a connection sup-
ported by the DeviceNet Communications Unit.
The following table shows the connection types and data sizes for OMRON DeviceNet Communications Units.
Note The size of the IN/OUT Areas depends on the setting.
DeviceNet I/O communications support the following types of connections.
Model Supported connections Data size (bytes)
Poll Bit strobe Change of
state (COS)
Cyclic IN OUT
K3HB-DRT Yes Yes Yes Yes 1 to 120
(See note.)
1 to 58
(See note.)
Connection type Details Remarks
Poll Used to exchange data between the master and
individual slaves by sending and receiving com-
mands and responses. (Output data is allocated
for commands and input data is allocated for
responses). ---
Bit strobe Used to broadcast commands from the master
and receive input responses from multiple
slaves. By using one command only, the communica-
tions cycle time is short, but bit strobe connec-
tions can be used only with slaves with 8 or less
input points.
Change of state
(COS) Normally, input and output data are sent by mas-
ter and slaves at regular cycles, but with a COS
connection, data is sent to the master or slave
when the master or slave data changes. By setting a long cycle interval, the Network will
not be loaded with communications for minor
data changes, thereby improving the overall effi-
ciency of the Network.
Cyclic Masters and slaves send output or input data at
regular cycles.