Packet Interval - Spectrum Controls 1769sc-IF4IH User Manual

7-10
Compact IO™ Isolated HART Analog Input Module
Figure 7-5 (Packet Ladder Continued)
User' s Manual 0300215-03 Rev. A
Note: The ladder in Figure 7-4 can be found in the project sample file located on our
website at (www.spectrumcontrols.com)

7.2.3 Packet Interval

The delay between two consecutive packets is called the packet interval. The default
time for the packet interval is 500 ms. This delay is controlled by the module.
The user has the ability to reduce the packet interval by utilizing output word 1 (HART
Packet Just Scanned) in the output image. See Table 7-6 (Module Output Table).
Copying the packet number just scanned to output word 1 allows the module to switch to
the next packet before the 500 ms delay expires. See Figure 7-4.
Note: The amount of time saved using this method depends on the scan time of the
ladder and the update time of each individual HART transmitter.