Keithley 2520, Руководство пользователя, Страница: 119 / 329

Model 2520 User’s Manual Triggering 8-3
Idle layer
The Model 2520 is in the Idle Layer when it is not operating in the Trigger Layer of the
trigger model. The Model 2520 can be returned to idle at any time by selecting the HALT
menu item of the CONFIGURE TRIGGER menu. See
“Configuring triggering,” page 8-7 .
Input triggers
The programmable trigger-in events for the Trigger Layer are described as follows:
IMMEDIATE
— Event detection occurs immediately allowing operation to continue.
GPIB
— Event detection occurs when a bus trigger (GET or *TRG) is received.
TIMER
— With the Timer selected, event detection occurs immediately when the output
is turned ON. On repeated passes via “Another Trigger? Yes”, event detection occurs when
the programmed timer interval expires. If operation takes the “Another Trigger? No” route,
the Timer resets allowing event detection to again occur immediately.
MANUAL
— Event detection occurs when the TRIG key is pressed.
TLINK
— Event detection occurs when an input trigger via the Trigger Link input line is
received (see “Trigger link,” page 8-5 , for more information).
↓
STEST
— Event detection occurs when the start-of-test (SOT) line of the Digital I/O
port is pulsed low. See Section 9 .
↑
STEST
— Event detection occurs when the SOT line of the Digital I/O port is pulsed
high. See Section 9 .
↑↓
STEST
— Event detection occurs when the SOT line of the Digital I/O port is pulsed
either high or low. See Section 9 .
Delay and pulse phases
The delay-pulse cycle consists of two phases: Delay and Pulse. (See Section 5 for com-
plete details.)
Delay phase
The programmable delay (set to between 20
µ
s and 500ms with the DELAY key) is the
time period between current pulses. Note, however, that the programmed delay is the min-
imum delay, and the actual delay depends on the pulse duty cycle (see
Section 5 ).