Keithley 199 Instruction Manual page 41

BASIC DMM OPERATION
2.7.6 LED lest
This program allows you to test all the front panel annun-
ciators and LED display segments to check for proper
operation. Proceed as follows:
1. Press DMM S!CTUP and then NEXT repeatedly until the
following message is displayed:
LEDS OFF
2. To test the LEDs, use uprange or downrange to toggle
the display to the following:
LEDS ON
3. Press NEXT to initiate the test.
4. During the test, the instrument will turn on all the an-
nunciators and walk through the various display
segments and complete displays to verify that ally are.
operating properly. Following the test, the instrument
will scroll to the next program.
2.7.7 Debug
The debug program is intended to switch various LED%
relays, and logic levels to allow signal tracing through the
instrument duing troubleshooting. Also, memory tests are
performed. For complete details on using the debug, refer
to paragraph 6.7.3.
To exit the diagnostic program, press any key except
TRIGGER.
2.7.8 Reset
The reset program restores iristrument setup parameters
to the factory default conditions listed in 'Tables 2-l and 3-7
Perform the following steps to use this program.
1. Press SHIFT DMM SETUP and then NEXT repeatedly
until the following message is displayed:
RESET NO
3. Press NEXT to reset the instrument, which will return
to the default conditions listed in Table 2-1.
NOTES~:
1. The reset program can be aborted by pressing NEXT
with the 'XESET NO" message displayed.
2. Once the instrument has been reset to default condi-
tions, use save setup to save that configuration if you
desire that the instrument power up in those conditions.
3. The reset program has no effect on the programmed
IEE~l%488 primary address or line frequency setting.
2.8 FRONT PANEL TRIGGERING
The following paragraphs discuss front panel triggering,
trigger mode selection, as well as trigger delay acd reading
interval programming.
2.8.1 Trigger Mode Selection
The Model 199 may be operated in two basic trigger modes:
one-shot and continuous. In the one-shot mode, a separate
trigger is required to initiate each reading. For the con-
tinuous mode, however, only a single trigger is required,
with the conversion rate determined by the programmed
reading interval. The continuous trigger mode is the fac-
tory default.
To check or change the selected trigger mode, proceed as
follows.
1. Press SHIFT TRIG SETUP. The instrument will display
the presently selected trigger mode. For the continuous
mode, the display will show:
coNTINuous
2. For the one-shot mode, the display
reads:
O~NE SHOT
3. TCtij@e the trigger mode, press uprange or dowruange.
4. Once the desired trigger mode is displayed, press NEXT
to scroll to the next menu selection (trigger delay), or
press NEXT to relurn to normal fronts panel display.
2.&e uprange or downrange to toggle the display as
follows:
RESFT YES
2-19