Topic: DMD0289
Setting the PLC Mode
Setting the operational mode of the Do-more CPU or the Do-more Simulator within Do-more Designer is done through the Set PLC Mode dialog. This dialog will send a Mode change request to the CPU. The CPU will process the request and change to the specified mode as long as there are no issues that prevent it from happening, like errors in the project currently loaded in the controller or a problem with the hardware.
The Set PLC Mode utility can be opened by selecting PLC -> PLC Modes from the menu, or using the key sequence Ctrl+Shft+Ror clicking the Mode button on the Online toolbar.
The Current PLC Status group displays:
PLC Mode: - displays the current operational mode: RUN or PROGRAM. The mode can also be seen programmatically in the $PLCMode (DST10): a value of 2 = STOP mode & 3 = RUN mode.
PLC Mode Switch Position: - displays the current position of the mode switch located on the front of the CPU: RUN, TERM, or STOP. The position of the Mode switch can be seen programmatically in the
The New PLC Mode group lists
the operation modes that are available:
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Run - the CPU will begin to run the project in its memory. Non-retentive memory will be cleared, retentive memory will not be changed, but the state information of all Programs (including their Stage bits) and Tasks have been reset even if the Program or Task has been configured as retentive.
-
Program - the CPU will stop executing the project in its memory.
Click OK to send the Mode change request to the CPU and close the dialog.
Click Cancel to close the dialog and leave the Mode unchanged.
The operational mode of the CPU can only be changed from Do-more Designer if the CPU's mode switch is in the TERM position. The Set PLC Mode dialog monitors the position of that switch and will only allow the mode change operation to take place when the switch is in the appropriate location. If the CPU's mode switch is in the RUN or STOP positions, the OK button will not be enabled. Follow this link for a detailed discussion of the CPU's mode switch.
See Also: