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.