2 CPU Unit Operation
2-26
NJ-series CPU Unit Software User’s Manual (W501)
When the CPU Unit changes from startup state to normal operation, it will change to the operating
mode that you specify in the Controller Setup. You can set the operating mode at startup to PRO-
GRAM mode or RUN mode. Thereafter, changing the operating mode causes the CPU Unit to
change between PROGRAM mode and RUN mode. If you download data from the Sysmac Studio
during PROGRAM mode, the CPU Unit will change to the downloading state. The CPU Unit will
return to PROGRAM mode when the download is completed.
• You can check the operating status of the CPU Unit with the status indicators on the front
panel of the CPU Unit. Refer to 11-1 Example Application for troubleshooting procedures
using the status indicators.
• Refer to A-5 Attributes of CPU Unit Data for information on data operations when the CPU Unit
status changes.
• Refer to 6-3-9 Changes to Variables for Status Changes for the values that variables take
when the status of the CPU Unit changes.
Power ON
Startup state
Normal operation
Controller error occurs
Error state
Controller error is reset.
RUN mode
PROGRAM
mode
Downloading
Operating mode is changed.
Software processing started.
Execution and comple-
tion of data download
from the Sysmac Studio.