Keithley 2001 Operator's Manual page 367

Programming example
Parameters
Format
Defaults
Query
2001-900-01 Rev. K / August 2010
Sending a value that exceeds the defined size of the buffer (see :POINts) will generate an error. The com-
mand will be ignored.
10 OUTPUT 716; ":trac:poin 75"
20 OUTPUT 716; ":trac:feed:pret:amo:read 30; read?"
30 ENTER 716; A$
40 PRINT A$
50 END
Line 10 Sets buffer size to 75 points.
Line 20 Two commands in this program message; the first specifies 30 buffer points for
pre-trigger readings, and the second queries the number of buffer points.
Line 30 Addresses the Model 2001 to talk.
Line 40 Displays the number of pre-trigger buffer points.
:SOURce [BUFFER,] <name>
:TRACe:FEED:PRETrigger:SOURce [BUFFER,] <name>Specify pre-trigger event
<name> = EXTernal
= TLINk
= BUS
= MANual
:trac:feed:pret:sour <name>
Power-up
*RST
:SYSTem:PRESet
:SOURce? [BUFFER,] Query buffer source.
Short-form format: :trac:feed:pret:sour?
Response message: EXT, TLIN, BUS or MAN
This command is used to specify the event for the pre-trigger storage mode. With the pre-trigger mode
selected (:CONTrol, PRETrigger), readings will be continuously stored in the buffer while waiting for
the pre-trigger source event.
With EXTernal source selected, an external trigger via the rear panel EXTERNAL TRIGGER Input will
provide the pre-trigger event.
With TLINk selected, an input trigger via the Trigger Link will provide the pre-trigger event. The Trigger
Link line used for the input trigger is programmed from the Trigger subsystem (see :TRIGger:TCONfig-
ure command path).
With BUS selected, a GPIB bus trigger (GET or *TRG) will provide the pre-trigger event.
With MANual selected, pressing the front panel TRIG key will provide the pre-trigger event.
Once the pre-trigger event occurs, the buffer will take (points - pre-trigger amount) more readings then
stop.
Use External Trigger as pre-trigger event
Use Trigger Link as pre-trigger event
Use bus trigger as pre-trigger event
Use TRIG key as pre-trigger event
MANual
No effect
No effect
IEEE-488 Reference
4-209