Mitsubishi MELSEC LJ71C24, User Manual

Page: 36 / 428

3 - 8 3 - 8
3 SPECIFICATIONS
Device
number
Signal description Reference
Device
number
Signal description Reference
X1A CH1 Global signal ON: Output instructed Y1A
X1B CH2 Global signal ON: Output instructed
MELSEC-Q/L
MELSEC
Communication
Protocol
Reference
Manual
Y1B
Use prohibited —
X1C
System setting default completion
ON: Completed
— Y1C
System setting default request
ON: Requesting
—
X1D 6 Predefined protocol ready ON: Ready Section 9.4 Y1D
X1E 4 C24 ready ON: Accessible — Y1E
X1F 5
Watchdog timer error (WDT error)
ON : Module error occurred
OFF: Module being normally operated
— Y1F
Use prohibited —
1 The device does not turn on/off by execution of a dedicated instruction when a
function that corresponds to the input signal is used.
2 The device does turn on/off by execution of a dedicated instruction when a function
that corresponds to the input signal is used (from ON to OFF: Data read completed).
3 The mode switching (X6/XD) turns ON when the following function is executed.
• Mode switching, transmission sequence initialization, reception data clear (by
buffer memory), user frame use enable/disable designation, UINI instruction,
programmable controller CPU information clear
While the mode switching (X6/XD) is ON, do not issue a communication request to
the target interface. (The communication processing of the C24 is stopped while
the mode switching (X6/XD) is ON.)
4 The C24 ready indicates whether or not it is possible to access the C24 from the CPU
module.
Use it as an interlock signal for a sequence program.
5 Restart the CPU module when the watchdog timer error is turned on.
If the error still occurs after restarting, refer to Section 15.3.1 to take corrective
actions.
6 Predefined protocol ready (X1D) is a signal that turns on when predefined protocol
communication becomes ready.
IMPORTANT
(1) Do not use any "use prohibited" signals as an output signal to the CPU
module.
Doing so may cause malfunction of the programmable controller system.
(2) If the modem function is not used, X10 to X16 and Y10 to Y16 cannot be used.