Specifications

HART ♦ ProLinx Gateway Functional Overview
HART Master Driver Manual
Page 18 of 119 ProSoft Technology, Inc.
July 7, 2009
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.