Keithley 2002, User Manual

Page: 64 / 366

Front Panel Operation
2-47
When the Model 2002 receives a trigger over the Trigger
Link, it performs a device action, as defined by the trigger
model. In addition to a measurement, this may include range
changing, filtering, calculations, data storing, scanning, and
other operations.
See paragraph 2.7.7 for details on using the Trigger Link.
NOTE
The front panel TRIG key (see MAN-
UAL) is active with the Trigger Link
selected. Pressing the TRIG key performs
a device action.
After selecting TRIGLINK as the measurement event, select
one of the following trigger link modes:
• ASYNCHRONOUS — The ascynchronous trigger link
mode is used for trigger configurations that require
input and output triggers to be routed on separate lines.
After selecting this trigger link mode, you will be
prompted to select an input line and then an output line.
Note that you cannot use the same trigger line for both
input and output.
• SEMI-SYNCHRONOUS — In this mode, the input and
output triggers for the Model 2002 are assigned to the
same line. After selecting this trigger link mode, you
will be prompted to select the trigger line.
TIMER: Use the timer to control the time interval between
measurements.
The timer can be set for an interval from 0.001 seconds
(1msec) to 999999.999 seconds with 1msec resolution.
After a measurement is triggered to start, the next measure-
ment starts at the end of the programmed timer interval. If
however, the programmed timer interval is shorter than the
time it takes to complete a single measurement, the next
measurement does not start until the previous one is done.
NOTE
The front panel TRIG key (see MAN-
UAL) is active with the timer selected.
Pressing the TRIG key after the comple-
tion of a measurement starts the next mea-
surement (assuming the Model 2002 is
programmed for another measurement;
see COUNT).
HOLD:
When HOLD is selected, the measure source is sup-
pressed. As a result, measuring is stopped and does not con-
tinue until HOLD is cancelled by selecting one of the other
measure source selections. Select HOLD from the SELECT
MEASURE SRC menu by placing the cursor on HOLD and
pressing ENTER. The instrument returns to the SETUP mea-
sure layer menu.
DELAY
This delay is used to hold up operation in the measure layer.
After the measure event occurs, the instrument waits until the
delay period times out (0 - 999999.999sec) before perform-
ing a device action.
COUNT
With this selection, you determine the number (count) of
measurements per scan sequence. The user programmed
count can be smaller, equal to, or larger than the number of
channels in the scan list. For example, if the scan list is made
up of four channels, you can program a count of 12. With this
count value, the instrument repeats the scan three times. An
advantage of repeating channels (rather than scans) is that
delays in the scan layer of operation are avoided. The mea-
sure delays among all 12 channels are the same.
INFINITE: Use this selection to continuously repeat mea-
surements (and looping in the measure layer).
ENTER-CHAN-COUNT: With this selection, the user
determines the number of readings per scan. You can pro-
gram the Model 2002 to measure up to 99999 times.
CONTROL
Use this menu item to enable or disable the source bypass.
The source bypass is used to bypass the measure event on the
first pass through the measure layer.
SOURCE: With this selection, the source bypass is enabled.
The measure event will be bypassed on the first pass through
the scan layer. This allows operation to proceed to the Delay
and Device Action without having to wait for the pro-
grammed event.
ACCEPTOR: With this selection, the source bypass is
disabled.