ProSoft Technology 5228-DFNT-HART - Manual (Page 24)

Functional Overview ProLinx-HART ♦ ProLinx Gateway
Driver Manual HART Master with Analog I/O
Page 24 of 104 ProSoft Technology, Inc.
October 13, 2011
The following topics describe the modes of module operation.
Auto-Poll Disabled Mode
If the auto-polling feature is disabled (Auto-Poll Code = N), the module functions as
shown in the following diagram:
Only the user commands are executed and all data is placed in and sourced from the
module's internal database. The user is responsible for constructing all commands to
control and monitor the instruments attached to the channel.
Point-to-Point Mode
Important: If the HART device address is 0 you must configure the channel for
Point-to-Point mode.
In point-to-point mode, the module only polls for a single instrument with a polling
address of zero. When the instrument is found by the channel, it continuously polls for the
data using command 3. Occasionally, it will poll for the configuration information for the
device. This is accomplished with HART commands 13, 14 and 15. Less frequently, the
channel will perform a HART command 0 request to see if any of the data for the
instrument has changed. If communications is lost with the device, the module will try to
establish communications with the device using command 0. If user commands are
present and enabled, they will be executed after each data poll.