Filter
Top Products
Logic Triggering
Reference
Table 3-4: Logic Triggers
Pattern
State Definition
1,2
AND Clocked AND If
all
the preconditions selected
for the logic inputs
3
are true,
then the oscilloscope triggers.
NAND Clocked NAND If
not all
of the preconditions se-
lected for the logic inputs
3
are
true, then the oscilloscope trig-
gers.
OR Clocked OR If
any
of the preconditions se-
lected for the logic inputs
3
are
true, then the oscilloscope trig-
gers.
NOR Clocked NOR If
none
of the preconditions se-
lected for the logic inputs
3
are
true, then the oscilloscope trig-
gers.
1
Note that for State class triggers, the definition must be met at the time the clock input
changes state. See the descriptions for Pattern and State in this section.
2
The definitions given here are correct for the Goes True setting in the Trigger When menu.
If that menu is set to Goes False, swap the definition for AND with that for NAND and for OR
with NOR for both pattern and state classes.
3
The logic inputs are channels 1, 2, 3, and 4 for the TDS 640A & TDS 644A and 1, 2, Aux 1
and Aux 2 for the TDS 620A & TDS 524A when using Pattern Logic Triggers. For State Logic
Triggers, channel 4 (Aux 2 for the TDS 620A & TDS 524A) becomes the clock input, leaving
the remaining channels as logic inputs.
The Logic Trigger menu (Figure 3-43) lets you select when to trigger (true or
false), set the thresholds for each channel, select the mode (auto or normal),
and adjust the holdoff.
Press TRIGGER MENU ➞ Type (main) ➞ Logic (pop-up) ➞ Class (main) ➞
Pattern or State (pop-up).
Operations Common
to Pattern and State