ProSoft Technology MVI69-HART - Manual (Page 98)

Reference MVI69-HART ♦ CompactLogix Platform
User Manual HART Multi-drop Master Communication Module
Page 98 of 169 ProSoft Technology, Inc.
March 29, 2012
Auto-Polling
This feature is enabled by setting the AUTO-POLL CODE (in the configuration
file) to a value of P (point-to-point). If the value N is entered for the parameter,
the auto-poll feature is disabled. When the feature is disabled, the channel will
only execute the commands enabled in the user command list. When the auto-
polling mode is enabled, the module will automatically acquire data from the
HART instruments attached to a channel without the use of user commands. If
user commands are present and enabled when the feature is enabled, they will
also be executed independent of auto-polling.
With the auto-poll feature enabled, the module automatically generates the
following HART commands and stores the data in the module's database at the
user-specified location:
CMD Description
0 Read Unique Identifier
3 Read Current and Four Dynamic Variables
13 Read Tag, Descriptor and Date
14 Read PV Sensor Information
15 Read Output Information
If the unit is set for point-to-point mode, the module will automatically gather the
information for the device with the polling address (short address) of zero and
place the data into the database. Each device requires a 50-word database area
with the format shown in the following table.
DB Byte
Offset Type Description Byte
Cnt Data
Source Use of Data
0 byte Auto-polling command status bits 1 App Status
1 byte Last first status byte received from
device
1 Resp Status
2 byte Last second status byte received
from device
1 Resp Status
3 byte Manufacture ID Code 1 CMD 0 LongAddress
4 byte Device Type Code 1 CMD 0 LongAddress
5 byte Minimum number of preambles 1 CMD 0 Msgconstruction
6 byte Universal Command Major Rev # 1 CMD 0 Msgchoice
7 byte Device Revision Level 1 CMD 0 Info
8 byte Software Revision Level 1 CMD 0 Info
9 byte Hardware Revision Level/Physical
Signaling Code
1 CMD 0 Info
10 byte Device Flags 1 CMD 0 Info
11 to 13 byte Device ID 3 CMD 0 Long Address
14 byte Minimum number of preambles to
be sent with the response message
from the slave to the master.
1 CMD 0
15 byte Maximum number of device
variables
1 CMD 0 Info
16 to 17 word Configuration Change Counter 2 CMD 0 Info