73
CPU Unit Operating Modes
Section 2-5
Note
When the mode is changed between PROGRAMMING mode and
RUN or MONITOR mode, forced status initialization is according to
the status of the Forced Status Hold Bit at that time.
(3) User program recovery is performed if online editing is performed but the
power supply to the PLC is turned OFF before the CPU Unit can complete
backup processing. The BKUP indicator will light during backup process-
ing.
2-5
CPU Unit Operating Modes
2-5-1
Operating Modes
The CPU Unit has three operating modes that control the entire user program
and are common to all tasks.
PROGRAM:
Programs are not executed and preparations, such as initial-
izing the PLC Setup and other settings, transferring pro-
grams, checking programs, force-setting and force-resetting
can be executed prior to program execution.
MONITOR:
Programs are executed, but some operations, such as online
editing, forced-set/reset, and changes to present values in I/O
memory, are enabled for trial operation and other adjust-
ments.
RUN:
Programs are executed and some operations are disabled.
2-5-2
Status and Operations in Each Operating Mode
The following table lists status and operations for each mode.
Note
The following table shows the relationship of operating modes to tasks.
Operation
PROGRAM mode
RUN mode
MONITOR mode
Program execution
Stopped
Executed
Executed
I/O refreshing
Executed
Executed
Executed
External I/O status
OFF
According to program
According to program
I/O memory
Non-holding memory
Cleared
According to program
According to program
Holding memory
Held
CX-Programmer
operations
I/O memory monitoring
OK
OK
OK
Program monitoring
OK
OK
OK
Program
transfers
From CPU Unit
OK
OK
OK
To CPU Unit
OK
X
X
Checking program
OK
X
X
Setting PLC Setup
OK
X
X
Changing program
OK
X
OK
Force-setting/resetting
OK
X
OK
Changing timer/counter SV
OK
X
OK
Changing timer/counter PV
OK
X
OK
Change I/O memory PV
OK
X
OK
Mode
Cyclic task status
Interrupt task
status
PROGRAM
Disabled status (INI)
Stopped
Summary of Contents for CP1L - 12-2007
Page 3: ...iv...
Page 9: ...x...
Page 13: ...xiv TABLE OF CONTENTS...
Page 21: ...xxii...
Page 33: ...xxxiv Conformance to EC Directives 6...
Page 65: ...32 Function Blocks Section 1 5...
Page 428: ...395 Clock Section 6 9...
Page 429: ...396 Clock Section 6 9...
Page 523: ...488 Troubleshooting Unit Errors Section 9 4...
Page 531: ...496 Replacing User serviceable Parts Section 10 2...
Page 563: ...528 Auxiliary Area Allocations by Function Appendix C...
Page 611: ...576 Auxiliary Area Allocations by Address Appendix D...
Page 638: ...603 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 639: ...604 Connections to Serial Communications Option Boards Appendix F...
Page 669: ...634 Index...
Page 671: ...636 Revision History...