228 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Appendix F MicroLogix 1400 Distributed Network Protocol
The number of elements for Frozen Counter Object is the same as the number
of Counter Objects. For example, if 10 Counter elements were configured, 10
Frozen Counter elements are generated in the controller internally. You
cannot access the Frozen Counter database directly.
There is one buffer for Frozen Counter Object. Read the Frozen Counter Object
before you send another request with Freeze function codes. If two
consecutive Freeze function codes are received without Read operation into
them for Frozen Counter Object, the values of Frozen Counter Objects are
overwritten by the second Freeze operation.
If both 16-bit Counter Object File Number and 32-bit Counter Object File
Number were configured in the DNP3 Slave Application Layer Configuration
file, the 16-bit Frozen Counter Object starting index number is 0 and the 32-bit
Frozen Counter Object starting index number of starts after the last index
number for 16-bit Frozen Counter Object. For example, if 10 elements of 16-bit
Counter Object were configured and 10 elements of 32-bit Counter Object were
configured, the index numbers are:
• 16-bit Frozen Counter Object: From 0…9
• 32-bit Frozen Counter Object: From 10…19
When only one of the Counter Object File was configured, Index number starts
from 0 for the configured object.
As an example, a Frozen Counter Config File is shown below. These files have
10 elements for each. B34:0/0 and B34:0/1 can be configured for Class Level 0, 1,
2 or 3 for DNP3 Index 0 of the 16 bits Frozen Counter Object File. B34:1/0 and
B34:1/1 can be configured for Class Level for DNP3 Index 1 of the Counter
Object File. Default Class Level is 0. Any other bits are reserved. So, in the
example below, for 16-bit Frozen Counter Config File, Class Level of Index 0 is
1(B34:0/0 and B34:0/1), Class Level of Index 1 is 2(B34:1/0 and B34:1/1), Class
Level of Index 2 is 3(B34:2/0 and B34:2/1), and Class Level of other Indexes
are 0.
To Next Page
Loading...
