Command 104 Write Burst Trigger sets the Unit Codes and levels used for Windowed and Level (Rising or Falling) trigger modes used in "Smart Device Publishing". A number of different configuration items (for example, changing the command being published/burst, the trigger mode, or the Device Variables being published) can affect the trigger classification, units, and value. There are Response Codes provided within the command specifications when this occurs. These Response Codes include:
Warning - Some burst settings may have been adjusted to support the new configuration.
Warning - Burst Trigger Mode has been automatically changed to a continuous trigger.
Command processing must be cognizant of these interactions and return the appropriate Response Codes (Success or Warning) accordingly.
In addition, When a Command 104 request is received, Device Variable Classification, Units Code, and Trigger Level shall be set to Not Classified (0); Not Used (250); and NaN (0x7F A0 00 00), respectively when setting Continuous or On-Change trigger modes.
See Common Practice Command Specification (FCG TS20151) for more information.
To assess field device proper processing of Burst Message configuration commands, CAL104A has been improved starting with HART Test System v3.6. More specifically, CAL104A now confirms for Continuous and On-Change trigger modes writing Not Classified (0); Not Used (250); and NaN (0x7F A0 00 00) results in "Success". See Attachment.