91
ICC
data_array[10] (deceleration time #1) has a value of 100 (10.0s),
data_array[11] (maximum frequency) has a value of 8000 (80.00Hz) etc.
13.2.9
ControlLogix Example: Read a Single Register
The configuration and execution for reading a single register is in general identical to
that required for reading a block of registers as detailed in section 13.2.8. The only
difference is in the configuration of the MSG instruction. Figure 104 shows an
example MSG instruction’s Configuration tab, which will read a single tag
(rd_reg_1402, which corresponds to the drive’s “inverter status 1” register) and place
it in the first element (offset 0) of data_array.
Figure 104: Read the Drive’s Status Register
13.2.10
ControlLogix Example: Multiple MSG Instructions
At times, reading from different groups of registers may be necessary. For example,
a specific application may require some registers located in various disjoint locations
in the register map. To accomplish this task efficiently, multiple MSG instructions
can be implemented in the PLC program.
The configuration and execution for implementing multiple MSG instructions is in
general identical to that required for implementing just one MSG instruction. Each
MSG instruction will require its own message controller tag. In the case of read MSG
instructions, more than one instruction may use the same Destination Element tag,
but the storage locations must not overlap. Figure 105 shows an example of two
MSG instructions, each accessing different read tags. It is evident from this logic
that “rd_connection” and “rd_connection2” are the two independent message
controller tags created for these instructions.