HEIDENHAIN TNC 306 Technical Manual - Manual (Page 300)

7-10
TNC 416/TNC 406/TNC 306 PLC-functions 3/2000
DISPLAY TRACE BUFFER
In the TNC 406 the trace buffer is immediately shown after the soft key TRACE is pressed
.
With the function DISPLAY TRACE BUFFER (TNC 306) 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 → (TNC 306) or the soft keys PAGE (TNC
406),
512 logic states before and after the trigger event can be observed.
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 40 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 PCTR blinks in the
status field. When the trigger event occurs, PCTR is on, and after the trace is stored, the display
goes out.
If marker M2622 is set the display COLL (TNC 306) or a symbol for a electrode (TNC 406) blinks.
END TRACE / STOP TRACE
If the trigger event does not occur, the trace can be aborted with the END TRACE or STOP TRACE
function. In this case, the last 1024 states of the selected operands are stored.
1.3.2 TABLE function
In the TABLE function the states of inputs (I), outputs (O), counters (C), timers (T), markers (M),
bytes (B), words (W) and double words (D) can be dynamically displayed on the screen.
The individual tables for inputs, outputs, etc. are selected with the corresponding letter (TNC 306), or
with a soft key (TNC 406).
The desired operand number is selected with the cursor keys.
The operands I/O/C/T/M can be changed with Set (S) or Reset (R), and in the TNC 406 Bytes (B),
Words (W) and Double words (D) can be overwrite, provided they are not defined through the PLC
program.
Bytes (B), Words (W) and Double words (D) can be displayed in HEX or in DECIMAL.
1.3.3 Debug Functions
This Debug function can be activated only on the TNC 406! Double words D308/D312/D316 make it
possible to display any memory area of the PLC in the PLC status window in up to three lines. The
values are hexadecimal coded. The function is activated by entering the starting address of the
marker area to be tested in D308/D312/D316. With K+0 in D308/D312/D316 the function is made
inactive. Byte markers appear as 80..FF with Marker =1, and 00..7F with Marker = 0.