Test and Measurement Forum

how to set trigger options in ps 3000

Post general discussions on using our drivers to write your own software here

how to set trigger options in ps 3000

Postby Guest » Thu May 10, 2007 8:23 am

HI,
The API provided with the ps3000 series has the ps3000_set_trigger() function. Can you please enlighten on how to set the "threshold" and "delay" parameters? is the threshold in mV or V setting?
Guest
 

Postby markB » Thu May 10, 2007 2:41 pm

The PS3000 manual states:

the threshold for the trigger event. This is scaled in 16-bit ADC counts at the currently selected range. If an external trigger is enabled the range is fixed at +/-20V.


threshold (16 bit ADC counts) = threshold (mV) * 32767 / inputRange(mV)

Therefore, if you have the 1V range selected and you want to trigger at 100mV the threshold will be:

100 * 32768 / 1000 = 3277 16 bit ADC counts
Regards

Mark
markB
Site Admin
Site Admin
 
Posts: 83
Joined: Tue Mar 27, 2007 9:43 am
Location: Cambridgeshire,UK

Re:

Postby Guest » Fri May 11, 2007 1:34 am

Hi, thanks for the reply.

How about the parameter on delay? I am using the example program streamingtest in C++ with the user interface. How should i determine what to be entered in the delay column?

Thanks and regards
Keeve
Guest
 

Postby markB » Mon May 14, 2007 8:35 am

Again, quoting the manual:

delay, specifies the delay, as a percentage of the requested number of data points, between the trigger event and the start of the block. It should be in the range -100% to +100%. Thus, 0% means that the trigger event is at the first data value in the block, and -50% means that it is in the middle of the block. If you wish to specify the delay as a floating-point value, use ps3000_set_trigger2() instead.
Regards

Mark
markB
Site Admin
Site Admin
 
Posts: 83
Joined: Tue Mar 27, 2007 9:43 am
Location: Cambridgeshire,UK


Return to General Software Discussions

Who is online

Users browsing this forum: No registered users and 0 guests