Tektronix TDS5054, Руководство пользователя

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Triggering
TDS5000 Series User Manual
3- 63
Timeout Trigger.
A timeout trigger occurs when the oscilloscope 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 inputs to the selected logic
function cause the function to become True or False. When you use a pattern
trigger, you define:
H
The precondition for each logic input: logic high, low, or “don’t care”; the
logic inputs are the oscilloscope channels
H
The Boolean logic function: AND, NAND, OR, or NOR
H
The condition for triggering: the Boolean function becomes True (logic high)
or False (logic low), and whether the True condition is time qualified
Pattern trigger logic choices are summarized in Table 3--5.
State Trigger. A state trigger occurs when the inputs to the logic function cause
the function to become True or False at the time the clock input changes state.
When you use a state trigger, you define:
H
The precondition for logic input channels 1 through 3 (channel 1 on
TDS5052)
H
The direction of the state change for the clock input, channel 4 (channel 2 on
the TDS5052)
H
The Boolean logic function: AND, NAND, OR, or NOR (not available on
the TDS5052)
H
The condition for triggering: the Boolean function becomes True (logic high)
or False (logic low)
State trigger logic conditions are summarized in Table 3--5.