Tektronix - page 168

Triggering
3-90 CSA7000 Series, TDS7000 Series, & TDS6000 Series Instruments User Manual
Transition Trigger. A transition (slew rate) trigger occurs when the trigger source
detects a pulse edge that transitions (slews) between two amplitude levels at a
rate faster or slower than you specify. The instrument can trigger on positive or
negative transitions. You can also think of transition triggering as triggering
based on the slope (change in voltage/change in time) of a pulse edge.
Timeout Trigger. A timeout trigger occurs when the trigger source does not detect
an expected pulse transition. If the pulse transition occurs prior to a specified
timeout time (the expected case), then no trigger results.
Pattern Trigger. A pattern trigger occurs when the logic inputs to the logic
function that you select cause the function to become TRUE (or at your option
FALSE). When you use a pattern trigger, you define:
HThe precondition for each logic input —logic high, low, or do not care (the
logic inputs are channels 1, 2, 3, and 4)
HThe Boolean logic function —select from AND, NAND, OR, and NOR
HThe condition for triggering —whether the trigger occurs when the Boolean
function becomes TRUE (logic high) or FALSE (logic low), and whether the
TRUE condition is time qualified
The pattern (and state) logic choices are summarized in Table 3--5.