5
- 55
5.3 The System Switching Function
5.3.5 Special Relays/Registers For System Switching
5
Set, – Not set
* 1 :
Does not store "1" in new standby system SD1601 when switching due to control system power OFF or reset.
Table5.39 Special Registers For System Switching (Continued)
Device
No.
Name
Description
Setting at Time of System Switching
New Control System
CPU Module
New Standby
System CPU Module
SD1600
System Fault
Information
• If an error occurs in the redundancy system error check, the following
corresponding bits turn ON. If the error is later cancelled, the bits turn OFF.
• If one of b0, b1, b2 and b15 turns ON, the others will turn OFF
• In Debug Mode, b0, b1, b2 and b15 are all OFF
SD1601
System Switching
Results
Stores system switching condition.
• Stores system switching condition in SD1601 on both systems at system
switching
• Initializes at 0 at power OFF
ON / reset
reset clear.
• The values stored in this register are as follows:
0: Initial value (system switching has never occurred)
1: Power OFF, reset, hardware failure or watchdog timer error
*1
2: Stop error (except watchdog timer error)
3: System switching request from network module
16: System switching instruction
17: System switching request from GX Developer
SD1602
System switching
dedicated
command
parameter
• Stores command parameter when switching due to SP.CONTSW
instruction.
(SP.CONTSW instruction parameter is stored in SD1602 on both systems
at system switching.)
• D1602 is only valid when "16: System switching instruction" is stored in
SD1601.
• SD1602 only changes during execution of system switching due to a control
system switching instruction.
SD1610
Other System
Diagnostic Error
The error code from the error occurring on the other system is stored in the bin
data.
The error code stored in the other system CPU module SD0 is stored here.
–
b1 b0
b15
b2
0 Fixed
Tracking cable loose or
damaged
0 : OFF
1 : ON
Powered down, reset,
watchdog timer, hardware
fault in the other system
Other system stop error
(excluding watchdog timer
error)
Unable to communicate with
other system.Communication
error is due to one of the
following.
Tracking hardware fault
Watchdog timer error has
occurred in this system
Unable to recognize
other system due to
other system fault
SD1600
Each Bit / Bits