User manual

Front Panel Operation
3-58 2001-900-01 Rev. K/ August 2010
Selecting BENCH or GPIB RESET from the SAVESETUP
option of the main menu sets the Delay to zero seconds.
As can be seen in the flowchart, there is a path that allows
operation to loop around the source. When Source Bypass is
enabled (Measure Trigger Control set to Source) and the
event source is External or Trigger Link, operation loops
around the source on the initial pass through the measure
layer. If programmed for another measurement (measure
count > 1), the bypass loop is not in effect even though it is
still enabled. The Source Bypass loop resets (is in effect) if
operation goes back into the scan layer.
At this point, a measurement is performed (Device Action).
Note that a Device Action could include, among others, a
function change, range change, or a channel scan (if scanner
is enabled). A channel is scanned (closed) before a
measurement is taken. When scanning channels, the
previous channel opens and the next channel closes (break-
before-make). In this case, the settling time delay for the
relay is included in the Device Action.
After a Device Action is performed, an Output Trigger
occurs. If the measure source is programmed for Immediate,
External, Manual, GPIB, or Timer, the output trigger pulse is
available at the METER COMPLETE connector. If the
Trigger Link source is selected, Output Trigger action occurs
as follows:
• If the asynchronous Trigger Link mode is selected, the
output trigger pulse is available on the programmed
TRIGGER LINK output line.
• If the semi-synchronous Trigger Link mode is selected
and the Source Bypass is disabled (Measure Trigger
Control set to Acceptor), the Trigger Link line is
released (goes high).
• If the semi-synchronous Trigger Link mode is selected
and the Source Bypass is enabled (Measure Trigger
Control set to Source), the Trigger Link line is pulled
low and then released.
NOTE
See paragraph 3.7.7 for details on using
the Trigger Link.
After the Device Action and an output trigger occurs, the in-
strument returns (if programmed to do so) to the beginning
of the measure layer to perform another measurement. The
Measure Count option is used to set the measure count to a
finite value (where n = 1 to 99999) or for an infinite number
of measurements. Selecting BENCH RESET from the
SAVESETUP option of the main menu sets the measure
count to infinite; selecting GPIB RESET sets the measure
count to one.
3.7.2 Configuring the measure layer
The measure layer is used for the following operations:
• To select the measuring event (SOURCE) for the
instrument.
• To delay operation in the measure layer.
• To designate the number of measurements the
instrument will make (COUNT).
• To enable or disable the Source Bypass.
Perform the following steps to display the measure layer
menu:
1. Display the CONFIGURE TRIGGER menu by pressing
the CONFIG key and then the TRIG key.
2. Use the cursor keys ( and ) to place the cursor on
MEASURE and press ENTER to access the following
menu:
SETUP MEASURE LAYER
SOURCE DELAY COUNT CONTROL
SOURCE
This menu item selects the event that controls the measure
source. To select it, place the cursor on SOURCE and press
ENTER. The following menu is displayed:
SELECT MEASURE SRC
IMMEDIATE EXTERNAL MANUAL
GPIB TRIGLINK TIMER HOLD
IMMEDIATE: With this selection, events (such as TIMER
and EXTERNAL triggers) do not control the measurement
interval. Once the Model 2001 starts measuring, it will take
readings as fast as its measurement configuration allows.
Select immediate triggering from the SELECT MEASURE
SRC menu by placing the cursor on IMMEDIATE and
pressing ENTER. The instrument returns to the SETUP
measure layer menu.
EXTERNAL: With this selection, external triggers are used
to control the measure source. Each trigger stimulus applied
to the Model 2001 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.
The external trigger is applied to the rear panel
“EXTERNAL TRIGGER” BNC connector. See paragraph
3.7.6 for detailed information on external triggering.
NOTE
Front panel TRIG key (see MANUAL) is
active with external triggering selected.