HEIDENHAIN TNC 335 Technical Manual - Manual (Page 389)

7-10
TNC 360 1 PLC Functions 8/95
DISPLAY TRACE BUFFER
With the DISPLAY TRACE BUFFER function the logic states 0 or 1 of the selected operands are
graphically displayed in a diagram. With simultaneous triggering, the counter is reset to 0 (upper left
in screen). By using the cursor keys
←
and
→
, 512 logic states can be observed before and after the
trigger event.
This can be used to determine, for example, whether a marker, output etc. was set too late or too
early. Taking the PLC processing time of 24 ms into account, a time displacement in ms can be
detected.
START TRACE
With this mode, TRACE is started. Until the trigger event occurs, the display PC TR blinks in the
status field. Then the display goes out.
END TRACE
If the trigger event does not occur, the trace can be aborted with the END TRACE function. In this
case, the last 1024 states of the selected operands are stored.
1.3.2 TABLE function
In the TABLES I/O/C/T/M function the states of inputs (I), outputs (O), counters (C), timers (T) and
markers (M) can be dynamically displayed on the screen. If the desired operand number is selected
with the cursor keys, the operand can be changed with Set (S) or Reset (R), provided that it was not
defined through the PLC program. The individual tables for inputs, outputs, etc. are selected with
the corresponding letter.
1.3.3 Transferring the PLC program PLC program
Data transmission can be activated with the EXT key from the main menu.
The following menu appears:
READ-IN SELECTED PROGRAM
OUTPUT ASCII
OUTPUT ASCII UNFORMATTED
OUTPUT ASCII WITH CROSS-REF
BINARY OUTPUT
PLC programs written on a computer can be transferred into the PLC RAM with the RS-232-C
interface. To load a program, select READ IN SELECTED PROGRAM. With the OUTPUT ASCII
function the PLC program can be transferred from the RAM to an external device. It can be
transferred with the cross references of all its operands.
It is also possible to transfer the program in unformatted or binary form by selecting the
corresponding menu items (see Section "Program creation", "EPROM creation").