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.

91