Omron CJ2 CPU UNIT SOFTWARE User Manual page 74

3 CPU Unit Operation
Output Status from Basic Output Units after Mode Change
When the operating mode is changed between RUN or MONITOR mode and PROGRAM mode with
the default settings, the outputs from Basic Output Units will be refreshed according to the I/O memory
status that exists when the mode is changed.
The output status for Basic Output Units will be as follows depending on whether IOM Hold Bit
(A500.12) is ON or OFF.
• If A500.12 is OFF, the output bits will be cleared when the mode is changed to PROGRAM mode,
and so the outputs from the Basic Output Units will turn OFF.
• If A500.12 is ON, the status of the output bits is held when the mode is changed to PROGRAM mode,
and so the status of the outputs from the Basic Output Units will also be held.
Precautions for Correct Use Precautions for Correct Use
Precautions for setting the IOM Hold Bit (A500.12) to ON
When the mode is changed from RUN or MONITOR mode to PROGRAM mode, the I/O memory
status of the outputs will not be cleared (i.e., turned OFF), and the status before changing to
PROGRAM mode will be held. Therefore, when changing the mode again from PROGRAM
mode to RUN or MONITOR mode, the I/O memory values before changing to PROGRAM mode
will be output.
If operation stops due to a fatal error (including execution of an FALS(007) instruction), however,
all outputs from the Basic Output Units will turn OFF even if the I/O memory status in the CPU
Unit is held.
3-12 CJ2 CPU Unit Software User's Manual