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ProSoft Technology 5228-DFNT-HART User Manual

Page 39

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ProLinx-HART ♦ ProLinx Gateway

HART Protocol Configuration

HART Master with Analog I/O

Driver Manual

ProSoft Technology, Inc.

Page 39 of 104

October 13, 2011

3.4.6 Delay Preset

This parameter sets an interval for each Data Map copy operation. The value you put for

the Delay Preset is not a fixed amount of time. It is the number of firmware scans that
must transpire between copy operations.
The firmware scan cycle can take a variable amount of time, depending on the level of

activity of the protocol drivers running on the ProLinx gateway and the level of activity on

the gateway's communication ports. Each firmware scan can take from 1 to several

milliseconds to complete. Therefore, Data Map copy operations cannot be expected to
happen at regular intervals.
If multiple copy operations (several rows in the Data map section) happen too frequently
or all happen in the same update interval, they could delay the process scan of the

gateway protocols, which could result in slow data updates or missed data on

communication ports. To avoid these potential problems, you should set the Delay Preset

to different values for each row in the Data Map section and set them to higher, rather
than lower, numbers.
For example, Delay Preset values below 1000 could begin to cause a noticeable delay in

data updates through the communication ports. And you should not set all Delay Presets
to the same value. Instead, use different values for each row in the Data Map such as

1000, 1001, and 1002 or any other different Delay Preset values you like. This will
prevent the copies from happening concurrently and prevent possible process scan

delays.

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