Omron CP1H CPU UNITS - PROGRAMMING 05-2007, Operation Manual

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Index Registers
Section 4-15
Limitations when Using Index Registers
• It is only possible to read the Index Register for the last task executed
within the cycle from the CX-Programmer. If using Index Registers with
the same number to perform multiple tasks, it is only possible with the CX-
Programmer to read the Index Register value for the last task performed
within the cycle from the multiple tasks, nor is it possible to write the Index
Register value from the CX-Programmer.
• It is not possible to either read or write to the Index Registers using Host
Link commands or FINS commands.
• A setting can be made from the CX-Programmer to share Index Registers
between tasks. This setting will be enabled uniformly for all Index Regis-
ters and Data Registers.
Sharing Index Registers The following setting can be made from the PLC Properties Dialog Box on the
CX-Programmer to control sharing Index and Data Registers between tasks.
Monitoring Index Registers
It is possible to monitor Index Registers as follows:
To use the Programming Devices to monitor the final Index Register values for
each task, or to monitor the Index Register values using Host Link commands
or FINS commands, write a program to store Index Register values from each
task to another area (e.g., DM area) at the end of each task, and to read Index
Register values from the storage words (e.g., DM area) at the beginning of
each task. The values stored for each task in other areas (e.g., DM area) can
then be edited using the CX-Programmer, Host Link commands, or FINS
commands.