Allen-Bradley PowerFlex 20-COMM-P FRN 1 Series User Manual page 55

32-Bit Parameters using 16-Bit Datalinks
To read (and/or write) a 32-bit parameter using 16-bit Datalinks,
typically both Datalinks (A,B,C,D) are set to the 32-bit parameter. For
example, to read Parameter 09 - [Elapsed MWh], both Datalink A1
and A2 are set to "9." Datalink A1 will contain the least significant word
(LSW) and Datalink A2 the most significant word (MSW). In this
example, the parameter 9 value of 5.8MWh is read as a "58" in Datalink
A1.
Datalink Most/Least Significant Word
A1 LSW
A2 MSW
Regardless of the Datalink combination, x1 will always contain the LSW
and x2 will always contain the MSW. In the following examples
Parameter 242 - [Power Up Marker] contains a value of 88.4541
hours.
Datalink Most/Least Significant Word
A1 LSW
A2 - Not Used -
Datalink Most/Least Significant Word
A1 - Not Used -
A2 MSW
Datalink Most/Least Significant Word
A2 MSW
B1 LSW
32-bit data is stored in binary as follows:
31
MSW 2 through 2
15
LSW 2 through 2
Example:
Parameter 242 - [Power Up Marker] = 88.4541 hours
MSW = 13 = 1101
decimal
LSW = 32573
851968 + 32573 = 884541
Parameter Data (decimal)
9
9
Parameter Data (decimal)
242
0
Parameter Data (decimal)
0
242
Parameter Data (decimal)
242
242
16
0
19 18
= 2 + 2 + 2
binary
Using I/O Messaging
58
0
32573
0
0
13
13
32573
16
= 851968
5-5