Mitsubishi MELSEC Q Series Programming Manual page 1264

Number Name
Reason(s)
for
Reason(s) for system
SD1588 system switching
switching that
occurred in
host station
Reason(s) for
Reason(s)
system
for system
SD1589 switching
switching
failure
failure No
conditions
Network Network
module head module head
address, address,
SD1590 which which
requested requested
system system
switching switching
Memory copy Memory
SD1595 target I/O copy target I/
number O number
Memory copy Memory
SD1596
status copy status
*1 The information of the host CPU module is stored.
App-256
Meaning
Stores the reason(s) for system switching on the host system. The
following values are stored corresponding to the methods for
system switching:
This register is initialized with zero (0) stored when the system is
powered on from off or is reset.
•0: Initial value (control system has never been switched)
•1: Power off, Reset, H/W failure, WDT error
•2: CPU stop error (except WDT)
•3: System switching request from network module
•16: System switching dedicated instruction
•17: System switching request from a programming tool
• If a system switching is failed, any of the following value is
stored in this register.
•0: System switching complete (default)
•1: Tracking cable is not connected, tracking cable failure, or
internal circuit failure
•2: H/W failure, power-off, reset, watchdog timer error on the
standby system
•3: H/W failure, power-off, reset, WDT error on the control
system
•4: Preparing tracking communication
•5: Communication timeout
•6: Stop error on the standby system (except for watchdog timer
error)
•7: Operation differs between both systems (detected only in the
back up mode)
•8: During memory copy from control system to standby system
•9: Performing program online change
•10: Detecting a failure of network module on the standby
system
•11: System is being switched
• Resets to "0" when host system is powered on.
• Zero is stored in this register upon completion of system
switching.
• When system switching is requested from a network module in
the host system, the bit corresponding to the module that
received the request turns on.
b15 to b11
0
SD1590 0/1
• The system turns off the bit after the error is removed by a user.
• For the number for modules where system switching is
requested from a network module in other system, refer to
SD1690.
• Before SM1595 is turned from off to on, the I/O No. of the
memory copy destination (Standby system CPU module: 3D1
is stored in this register.
• Stores the execution result of Memory copy function.
•0: Memory copy is complete
•4241 : Standby system power supply off
H
•4242 : Tracking cable is disconnected or is damaged
H
•4247 : Memory copy is being executed
H
•4248 : Unsupported memory copy destination I/O number
H
Explanation
Each bit
to b1 b0
0:OFF
0/1 0
1:ON
Module 0: CPU module is invalid
as it is 2-slot model
Module 1: Module on right side of
CPU module
to
Module11: Module at rightmost
end of 12-slot base
(Q312B)
Corres-
ponding
Set by
ACPU
(When Set)
D9
S
(when
condition
occurs)
S
(when system
is switched)
S
(Error/Status
change)
New
)
U
H
S
(Status
change)
Corres-
ponding
CPU
QnPRH