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Appendix F: Search and Trigg er Command Sequence Examples Example 2: Sin gle Threshold Edge T rigger Goal: Trig ger on the channel 2 waveform when the waveform crosses below a threshold of 1.4 volts. Command Comment *RST…

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Appendix F: Search and Trigger Command Sequence
Examples
The following are some example command sequences that show a variety of
different searches and triggers. The commands in these sequences are not
order-dependent.
To use these examples, connect channel 1, channel 2, channel 3 and channel 4 to
the probe compensation signal located on the right hand side of the front panel.
The search and trigger command group sections contain more information on
general search and trigger concepts. (See page 2-61, Search Command Group.)
(See page 2-76, Trigger Command Group.)
Example 1: Single Threshold Edge Search
Goal: Search the channel 2 waveform and place a mark at each instance where it
crosse
s below a threshold of 1.4 volts.
Command Comment
*RST Resets the oscilloscope. Wait for the reset to complete
(appr
oximately 3 seconds).
:SEL
ect:CH2 1
Turn
s the CH2 waveform on.
:AUT
OSet EXECute
Auto
sets the displayed waveform CH2. Wait for the autoset to
complete (approximately 3 seconds).
:SEARCH:SEARCH1:TRIGger:A:TYPe EDGE Specifies that this will be an edge search (a mark will be placed
when the s ource waveform passes through a specified threshold
lev
el in the specified direction).
:S
EARCH:SEARCH1:TRIGger:A:EDGE:SOUrce CH2
Sp
ecifies the CH2 waveform as the source wa veform.
:S
EARCH:SEARCH1:TRIGger:A:LOWerthreshold:CH2 1.4
Sp
ecifies 1.4 volts as the threshold level.
:
SEARCH:SEARCH1:TRIGger:A:EDG E:SLOpe FALL
S
pecifies the falling edge as the direction.
:
SEARCH:SEARCH1:STATE 1
Turns the search on.
:SEARCH:SEARCH1:TOTal? Returns 4, indicating that CH2 fell below the 1.4 volt threshold 4
times.
:SEARCH:SEARCH1:LIST? Returns a list of the 4 marks:
CH2,11.2411,11.2411,11.2411,-1.5504E-3,
0.0E+0,0.0E+0,0.0E+0;CH2,37.0737,37.0737,37.0737,
-517.0517E-6,0.0E+0,0.0E+0,0.0E+0;CH2,62.9163,62.9163,62.9163,
516.6517E-6,0.0E+0,0.0E+0,
0.0E+0;CH2,88.7489,88.7489,88.7489,
1.5500E-3,0.0E+0,0.0E+0,0.0E+0
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual F-1
Appendix F: Search and Trigger Command Sequence Examples
Example 2: Sin
gle Threshold Edge Trigger
Goal: Trigger on the channel 2 waveform when the waveform crosses below a
threshold of 1.4 volts.
Command Comment
*RST Resets the oscilloscope. Wait for the reset to complete (approximately
3 seconds).
:SELect:CH2 1 Turns the CH2 waveform on.
:TRIGger:A:TYPe EDG E Specifies that this will be an edge trigger (trigger will occur when the
source waveform passes through a specified threshold level in the
specified direction).
:TRIGger:A:EDGE:SOUrce CH2 Specifies the CH 2 waveform as the source waveform.
:TRIGger:A:LOWerthreshold:CH2 1.4 Specifies 1.4 volts as the threshold level.
:TRIGger:A:EDGE:SLOpe FALL Specifies as falling edge as the direction.
:TRIGger:STATE? Should return TRIGGER, not A UTO.
Example 3: Dual Threshold Runt Search
Goal: Search the channel 3 waveform for negative runt pulses and place a markat
each
instance when the waveform drops below an upper threshold of 1.4 volts, but
does not cross a lower threshold of -2 volts before re-crossing the upper threshold.
The pulse width must be less than 600 microseconds.
Com
mand
Com
ment
*R
ST
Re
sets the oscilloscope. Wait for the reset to complete
(approximately 3 seconds).
:SELect:CH3 1 Turns the CH3 waveform on.
:AUTOSet EXECute Autosets the displayed waveform CH3. Wait for the autoset to
complete (approximately 3 seconds).
:SEARCH:SEARCH1:TRIGger:A:TYPe RUNT Specifies that this will be a runt search (a mark will be placed on
a pulse amplitude that crosses one threshold but fails to cross a
second threshold before re-crossing the first).
:SEARCH:SEARCH1:TRIGger:A:EDGE:SOUrce CH3 Specifies to use channel 3 as the source waveform.
:SEARCH:SEARCH1:TRIGger:A:LOWerthreshold:CH3 -2 Specifies to use -2 volts as the lower threshold.
:SEARCH:SEARCH1:TRIGger:A:UPPerthreshold: CH3 1.4 S pecifies to use 1.4 volts as the upper threshold.
:SEARCH:SEARCH1:TRIGger:A:RUNT:PO Larity NEGative Specifies to search for when the runt polarity is negative.
:SEARCH:SEARCH1:TRIGger:A:RUNT:WIDth 600E-6 Specifies a pulse width of 600E-6 seconds.
:SEARCH:SEARCH1:TRIGger:A:RUNT:WHEn LESSthan Specifies to search for when the pulse width is less than
600E-6 seconds.
:SEARCH:SEARCH1:STATE 1
Turns the search on.
F-2 MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual
Appendix F: Search and Trigger Command Sequence Examples
Command Comment
:SEARCH:SEARCH1:TOTal?
Returns 3, ind
icating that 3 total negative runt pulses were less than
600E-6 seconds wide
:SEARCH:SEARCH1:LIST? Returns a list of 3 marks:
CH3,11.2311,24.1624,24.1624,1.0335E3,0.0E+0,0.0E+0,0.0E+0;CH3,37.0837,
50.0150,50.
0150,600.0600E9,0.0E+0,0.0E+0,0.0E+0;CH3,62.9263,75.8576,
75.8576,1.0343E-3,0.0E+0,0.0E+0,0.0E+0
NOTE. You could use a similar command sequence with a transition type search.
Example 4: Single Threshold Logic Search on Three Wa veform s
Goal: Search the channel 1, 2 and 3 waveforms and place a mark at each instance
when either channel 1 is above 1.4 volts, channel 2 is above 1.5 volts, or channel
3 is above 1.3 volts.
Command Comment
*RST Resets the oscilloscope. Wait for the reset to complete
(approximately 3 seconds).
:SELect:CH1 1 Turns the C H1 waveform on.
:SELect:CH2 1 Turns the C H2 waveform on.
:SELect:CH3 1 Turns the C H3 waveform on.
:AUTOSet EXECute Autosets the displayed waveforms CH1, CH2 and CH3. Wait
for the autoset to complete (approximately 3 seconds).
:SEARCH:SEARCH1:TRIGger:A:TYPe LOGIc Specifies that this will be a logic search (a mark will be placed
when all channels transition to the specified state).
:SEARCH:SEARC H1:T RIG ger:A:LOGIc:INPut:CH1 HIGH Specifies the Boolean logic criteria for channel 1; in this case,
high.
:SEARCH:SEARC H1:T RIG ger:A:LOGIc:INPut:CH2 HIGH Specifies the Boolean logic criteria for channel 2; in this case,
high.
:SEARCH:SEARC H1:T RIG ger:A:LOGIc:INPut:CH3 HIGH Specifies the Boolean logic criteria for channel 3; in this case,
high.
:SEARCH:SEARCH1:TRIGger:A:LOGIc:THReshold:CH1 1.4 Specifies to use 1.4 volts as the threshold for CH1.
:SEARCH:SEARCH1:TRIGger:A:LOGIc:THReshold:CH2 1.5 Specifies to use 1.5 volts as the threshold for CH2.
:SEARCH:SEARCH1:TRIGger:A:LOGIc:THReshold:CH3 1.3 Specifies to use 1.3 volts as the threshold for CH3.
:SEARCH:SEARC H1:T RIGger:A:LOGIc:PATtern:WHEn TRUE Specifies the c ondition for generating a logic pattern search;
in this case, true.
:SEARCH:SEARC H1:T RIGger:A:LOGIc:FUNCtion OR Specifies the logic operator for the logic search; in this case,
OR.
:SEARCH:SEARCH1:STATE 1
Turns the search on.
MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual F-3