Keithley 2002 User Manual page 72

For this example, the Models 2002 and 7001/7002 are con-
figured as follows:
Model 2002:
Idle state:
Bench reset = :INIT:CONT ON*
Arm layer:
Arm source = Immediate*
Arm count = 1*
Arm trigger control = Acceptor*
Scan layer:
Scan source = Immediate*
Scan count = Infinite*
Scan trigger control = Acceptor*
Measure layer:
Measure source = TrigLink
Trigger link mode = Asynchronous*
Input line = #2*
Output line = #1*
Measure count = 10
Measure trigger control = Acceptor*
* Indicates that the setting is the BENCH RESET (and factory) default con-
dition.
Model 7001 or 7002:
Idle state:
Reset = :INIT:CONT OFF*
Scan list = 1!1-1!10,
Arm layer:
Arm spacing = Immediate*
Arm count = 1*
Arm trigger control = Acceptor*
Scan layer:
Scan spacing = Immediate*
Number of scans = 1
Scan trigger control = Acceptor*
Channel Layer:
Channel spacing = TrigLink
Trigger link mode = Asynchronous*
Input line = #1*
Output line = #2*
Number of channels = Use Scanlist length*
Channel trigger control = Source*
* Indicates that the setting is the RESET (and factory) default condition.
Notice that the Model 2002 is reset to BENCH defaults. With
this selection, the multimeter stays armed. Since the arm
source and scan source are set to Immediate, the Model 2002
waits in the measure layer for a trigger.
With the Channel Trigger Control of the Model 7001/7002
set for Source, scan operation initially bypasses the need for
a Trigger Link trigger to close the first channel. Since arm
spacing and scan spacing are set to Immediate, the scan starts
as soon as the scanner is taken out of the idle state by press-
ing the STEP key.
To run the test and store the readings in the Model 2002,
press STORE on the multimeter, enter the desired number of
readings (ten), 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
scanner's output pulse triggers the Model 2002 to take a
reading, store it, and send a trigger pulse. The following ex-
planation on operation is referenced to the operation model
shown in Figure 2-21.
A
The BENCH RESET condition arms the Model 2002
and places multimeter operation at point A in the flowchart,
where it is waiting for a Trigger Link trigger. Note that since
both the arm layer and scan layer are programmed for Imme-
diate Source, operation immediately drops down to the mea-
sure layer at point A.
B
Pressing STEP takes the Model 7001/7002 out of the
idle state and places operation at point B in the flowchart.
Since both the arm layer and scan layer are programmed for
Immediate Spacing, operation drops down to the channel
layer at point B.
C
Since Channel Trigger Source is set to Source, the
scan does not wait at point B for a trigger. Instead, it bypass-
es "Wait for Trigger Link Trigger" and closes the first chan-
nel (point C). Note that the Bypass is in effect only on the
first pass through the model into a layer.
D
After the relay settles, the Model 7001/7002 outputs a
Channel Ready pulse (point D). Since the instrument is pro-
grammed 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 F
and Remember that the Model 2002 operation is
at point A waiting for a trigger. The output Channel Ready
pulse from the Model 7001/7002 triggers the multimeter to
measure DUT #1 (point E). After the measurement is com-
plete, the Model 2002 outputs a completion pulse (point F)
and then loops back to point A, where it waits for another in-
put trigger.
The trigger applied to the Model 7001/7002 from the Model
2002 closes the next channel in the scan. This triggers the
multimeter to measure the next DUT. The process continues
until all ten channels are scanned and measured.
Front Panel Operation
2-55