Rockwell Automation Allen-Bradley 842D, Руководство пользователя

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5-6 Configuring a Scanner to Communicate with the Encoder
Figure 5.4 Edit I/O Parameters Dialog Box - COS
9. Select the type(s) of data exchange (Polled, Change of State,
and/or Cyclic). In our example, we selected Change of State.
10. Type the number of bytes that will be required for your I/O in the
Rx Size and Tx Size. See
Assembly Data Format , page B-4, for
data sizes.
11. Set the scan rate:
Click Help for more information.
12. When using COS in high speed and/or high resolution
applications, it may be necessary to limit how often the device
will report to the master in order to lessen network traffic. To do
so requires either setting the hysteresis to over 10% of the
‘RESOLUTION PER REVOLUTION’ value or increasing the
‘Inhibit Time’. To increase the inhibit time to 10ms, click on the
Advanced... button under ‘Change of State/Cyclic.’ Adjust the
Inhibit Time and click OK .
Data
Exchange
Rate to set
Polled Polled Rate
Change of
State Heartbeat
Rate
Cyclic Send Rate