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Entry  Sun Sep 23 02:22:46 2018, Gerard Arino-Estrada, Trigger OUT pulse width variable from 100 us up to 100 ms 
    Reply  Wed Sep 26 14:44:14 2018, Stefan Ritt, Trigger OUT pulse width variable from 100 us up to 100 ms 
       Reply  Wed Sep 26 18:28:20 2018, Gerard Arino-Estrada, Trigger OUT pulse width variable from 100 us up to 100 ms 
          Reply  Wed Sep 26 19:21:03 2018, Stefan Ritt, Trigger OUT pulse width variable from 100 us up to 100 ms 
Message ID: 720     Entry time: Wed Sep 26 18:28:20 2018     In reply to: 718     Reply to this: 721
Author: Gerard Arino-Estrada 
Subject: Trigger OUT pulse width variable from 100 us up to 100 ms 

Thank you very much for the answer, I really appreciate your help.

Thanks!

Gerard

Stefan Ritt wrote:

The "Trigger OUT" has changed recently. It goes high on a new trigger, but then STAYS high until the board has been read out by the PC and re-started. This allows better synchronization with some external trigger, which can be re-armed with the falling edge of the trigger out signal. The signal can be quite long, since readout of an event via USB typically takes 2 ms, but can be more if the PC is busy. If you need back your 150 ns pulse, send the trigger out to an external pulse shaper with fixed shaping width.

Stefan

Gerard Arino-Estrada wrote:

Hello Stefan,

I am using the DRS4 board connected to a Raspberry PI and through the drsosc application. I am interested on using the "Trigger OUT" signal to do some extra data processing with NIM modules. According to the manual, for each hardware trigger a TTL pulse of 150 ns width should be send through the "trigger OUT". In my case I do see pulses with widths ranging from 100 microseconds up to hundreds of miliseconds. I am connecting the signal directly to an oscilloscope with 50 Ohm termination. I have tried two DRS4 boards in identical conditions and both show the same behavior.  Having such wide and variable pulses makes it complicated for me to do the extra post-processing. Have you any idea of what might be going wrong? Thank you very much.

Best regards,

Gerard

 

 

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