Keithley 2002 User Manual page 76

To run the test and store the readings in the Model 2002,
press STORE on the multimeter, enter the desired number of
readings (20), and press ENTER. The Model 2002 waits
(with the asterisk annunciator lit) for a Trigger Link trigger
from the Model 7001/7002.
Press STEP on the Model 7001/7002 to start the scan. The
following explanation on operation is referenced to the oper-
ation model shown in Figure 2-25.
A
Pressing STEP on the Model 7001/7002 takes it out of
the idle state and places operation at point A in the flowchart.
Since the arm layer is programmed for Immediate Spacing,
operation drops down to the scan layer at point A.
B
Since Scan Trigger Control of the Model 7001/7002 is
set for Source, the scan does not wait at point A for a trigger.
Instead, it bypasses "Wait for Trigger Link Trigger" and pro-
ceeds to point B. Note that this Bypass is in effect only on the
first pass through the model.
C
Since Channel Trigger Source of the Model 7001/
7002 is also set to Source, the scan does not wait at point B
for a trigger. Instead, it bypasses "Wait for Trigger Link Trig-
ger" and closes the first channel (point C). Note that the By-
pass is in effect only on the first pass through the model.
D
After the relay settles, the Model 7001/7002 outputs a
Trigger Link trigger pulse (point D). Since the instrument is
programmed to scan ten channels, operation loops back up to
point B, where it waits for an input trigger. Note that Bypass
is no longer in effect.
E
The trigger pulse from the Model 7001/7002 triggers
the Model 2002 to make a measurement of DUT #1. After
the measurement is complete, the multimeter outputs a Trig-
ger Link trigger pulse (point E).
The trigger applied to the Model 7001/7002 from the Model
2002 closes the next channel in the scan, which in turn trig-
gers the multimeter to measure the next DUT. This process
continues until all ten channels are scanned and measured.
F
After the last channel is scanned and measured, oper-
ation proceeds to point F, where the Model 7001/7002 out-
puts a trigger pulse. Since the Model 7001/7002 is
programmed to perform two scans, its operation loops back
up to point A, where it waits for an input trigger. Note that
Bypass is no longer in effect.
G
The trigger pulse from the Model 7001/7002 triggers
the Model 230 to output the next programmed voltage level.
After the voltage level is set, the Model 230 outputs a trigger
pulse (point G).
The trigger pulse applied to the Model 7001/7002 from the
Model 230 places operation at point B. The Bypass is again
in effect because this is the beginning of a new scan. This al-
lows operation to drop down to point C, where the first chan-
nel is again closed and eventually measured. As previously
explained, all ten channels are scanned and measured.
After the last channel of the second scan is closed and mea-
sured, the Model 7001/7002 returns to the idle state.
Front Panel Operation
2-59