X20 system modules • Analog input modules • X20AI2438
220
X20 system User's Manual 3.10
4.3.7.9.8.4 Extended configuration
The additional configuration registers are specified values when the module is started. In most systems, the user
does not need to make any adjustments here. Register values should only be changed if HART network commu-
nication is not taking place satisfactorily.
HartNodeDisable
The "HartNodeDisable" registers are intended for things like maintenance. They make it possible to cut off config-
ured HART nodes to suppress error messages for a certain period of time. During normal operation, the configured
nodes must be switched active to guarantee that the procedure runs smoothly.
Data type
Values
UINT
See bit structure
Bit structure:
Bit
Name
Information
0
Enabled (bus controller default)
0
Node 0 (default mode)
Node 1 (multidrop mode)
1
Disabled
0
Enabled
1
Node 2 (multidrop mode)
1
Disabled (bus controller default)
...
0
Enabled
13
Node 14 (multidrop mode)
1
Disabled (bus controller default)
0
Enabled
14
Node 15 (multidrop mode)
1
Disabled (bus controller default)
15
Reserved
-
HartProtTimeOut
The "HartProtTimeOut" registers specify the time span within which the slave must respond for the response to
be valid.
Data type
Values [ms]
UINT
0 to 65535
Bus controller default: 256 [ms]
HartProtRetry
The "HartProtRetry" registers how many times the master retries a request if it receives an invalid response or
no response at all.
Data type
Values
UINT
0 to 65535
Bus controller default: 3 attempts
HartPreamble
The length of the preamble can be set in the "HartPreamble" registers. The preamble is used to synchronize the
receiver to the transmitter. The longer the declared preamble, the less chance that a communication error will
occur. Nevertheless, a useful signal is not transmitted during synchronization so the preamble should be kept as
short as possible.
Data type
Values
UINT
5 to 20
Bus controller default: 20