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MELSEC-Q
7 FUNCTION
3) At the "Trace Condition" section, select one of the following:
• Execute by overwriting the conditions on PLC side.
Overwrites trace condition to the existing trace file.
• Execute by following conditions written on PLC side
Executes the program with the conditions in the trace file specified in
"Trace Data (Con Results) storing dest".
(e) Read the trace results form the High Performance model QCPU and display
the data.
1) "Read from PLC" reads the trace result from the High Performance
model QCPU.
2) The read trace results appears in "Trace results" display.
POINT
Sampling trace is executed only once.
When re-executing, execute the TRACE instruction, and reset the sampling trace.
(3) Precautions
(a) SRAM card is required for sampling trace.
Set the sampling trace file in the memory card (SRAM).
(b) The sampling trace can be executed from other station on the network or
serial communication module. However, the trace cannot be executed from
multiple areas at once. The trace can only be executed from one area with
High Performance model QCPU.
(c) The trace information (trace file) registered in the High Performance model
QCPU is registered in the SRAM card and latched. As the condition data is
stored in the trace file, even if the power is off or the High Performance
model QCPU is reset, the sampling trace can be executed under registered
trace conditions.
At power on/reset of High Performance model QCPU, latched trace
information is cleared in the cases where:
• The SRAM card registered in a trace file is not inserted
• The trace file is corrupted
This requires registering trace information once again by operating from
GX Developer.
To clear data, perform the latch-clear operation with the RESET/L.CLR
switch.
To perform sampling trace again after latch clear, execute sampling trace
after selecting "Regist trace".
(d) This is performed by connecting the High Performance model QCPU and
GX Developer.
(e) While in STOP status, the High Performance model QCPU cannot read
sampling trace results. To enable the High Performance model QCPU to
read the sampling trace results, enter the High Performance model QCPU
into RUN status.
(f) When executing the sampling trace, ensure that trigger conditions cannot
be satisfied at trigger points. If the trigger conditions are met when
executing the sampling trace, they will not be recognized as trigger
conditions.