Tektronix TDS 500C Graphics Tablet User Manual


 
Triggering on Waveforms
TDS 500C, TDS 600B, & TDS 700C User Manual
3–83
To Define the Logic. To choose the logic function you want applied to the input
channels (see page 3–77 for definitions of the logic functions for both pattern
and state triggers):
Press TRIGGER MENU Type (main) Logic (pop-up) Class (main)
Pattern (pop-up) Define Logic (main) AND, OR, NAND, or NOR (side).
Set Trigger When. To choose to trigger when the logic condition is met (Goes
TRUE) or when the logic condition is not met (Goes FALSE), do the following
step:
Press TRIGGER MENU Type (main) Logic (pop-up) Class (main)
Pattern (pop-up) Trigger When (main) Goes TRUE or Goes FALSE
(side).
The side menu items TRUE for less than and TRUE for greater than are used to
time qualify a pattern trigger. See the procedure Define a Time Qualified Pattern
Trigger that follows for instructions.
To Set Mode and Holdoff. Mode and holdoff can be set for all standard trigger
types and classes. To set mode and holdoff, refer to To Set Mode & Holdoff on
page 3–75. To learn more about trigger mode and holdoff, see the descriptions
Trigger Modes and Trigger Holdoff on page 3–65.
You can also time qualify a pattern logic trigger. That is, you specify a time that
the boolean logic function (AND, NAND, OR, or NOR) must be TRUE (logic
high). To specify the time limit as well as the type of time qualification (greater
or less than the time limit specified) for a pattern trigger, do the following steps:
1. Press TRIGGER MENU Type (main) Logic (pop-up)
Class (main) Pattern (pop-up) Trigger When (main) TRUE for
less than or TRUE for more than (side).
2. Use the knob and keypad to set the time in the side menu.
When you select TRUE for less than and specify a time, the input conditions you
specify must drive the logic function high (TRUE) for less than the time you
specify. Conversely, the TRUE for more than menu item requires the boolean
function to be TRUE for longer than the time you specify.
To Define a Time Qualified
Pattern Trigger