Using the CCM protocol with a GE 9030 PLC, the following remapping could be used to optimize communication when reading some digital register values. This example is based on the assumption that the PLC is set up correctly for remapping.
Variable tags database
The digital register values are defined as follows.
|
Variable Tag Name |
Motor_1_Running_Feedback |
|
Data Type |
Digital |
|
I/O Device Name |
Area1 |
|
Address |
M1 |
|
Variable Tag Name |
Motor_1_Overload |
|
Data Type |
Digital |
|
I/O Device Name |
Area1 |
|
Address |
M3 |
|
Variable Tag Name |
Motor_4_ Running_Feedback |
|
Data Type |
Digital |
|
I/O Device Name |
Area1 |
|
Address |
M4 |
|
. |
|
|
. |
|
|
. |
|
|
Variable Tag Name |
Motor_4_ Running_Feedback |
|
Data Type |
Digital |
|
I/O Device Name |
Area1 |
|
Address |
M16 |
Notice that the address M2 is not used. Skipping addresses does not affect performance.
Remapping database
The remapping is defined as follows.
|
CitectSCADA Variable |
Area1|M1| |
|
Length |
16 |
|
Physical Variable |
Area1|R10| |
|
Remap Read |
True |
|
Remap Write |
False |
The physical variable is an integer data type; it does not need to be defined in the variable tags database (but it can be).