HEIDENHAIN TNC 335 Technical Manual - Manual (Page 388)

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TNC 360 1 PLC Functions 7-9
1.3 Test functions for the PLC program
1.3.1 TRACE function
The TRACE function makes it possible to check the logical states of the markers, inputs, outputs,
timers and counters.
If this function is selected, the following menu appears:
SELECT I/O/C/T/M
DISPLAY TRACE BUFFER
START TRACE
END TRACE
SELECT I/O/C/T/M
Those inputs (I), outputs (O), counters (C), timers (T) or markers (M) whose logical states are to be
checked can be entered into a table in the SELECT I/O/C/T/M function. A maximum of 16 markers,
timers etc. can be simultaneously verified. Each position is interrogated via dialogue. Erroneous
entries can be deleted by pressing DEL.
The memory for the trace mode (TRACE BUFFER) has space for 1024 individual states per operand,
i.e. 1024 PLC processes are recorded. In order to record the required time duration of the user, a
TRIGGER condition can be entered for each operand:
"1" = Recording when operand is logically "1"
"0" = Recording when operand is logically "0"
If the trigger position is verified with the NOENT key, it means that a trigger condition is not
required. 512 states are recorded before and after a trigger event. The trigger event is regarded as
fulfilled only when the conditions for all operands are simultaneously fulfilled with TRIGGER.
Example: M2064 1
M2065 0
M2066 1
I5
Trigger event:
M2064 logical "1"
M2065 logical "0"
M2066 logical "1"
The state of I5 has no significance for the trigger event: it is, however, recorded.
If no trigger condition is entered for the operands, the states of the operands are continually
recorded and, after ending the trace mode, the last 1024 states are displayed.
To exit the SELECT I/O/C/T/M function, press END.