DRS4 Forum
  DRS4 Discussion Forum  Not logged in ELOG logo
Entry  Wed Mar 7 22:49:38 2018, Rodrigo Trindade de Menezes, Running drs_example.cpp drs_exam.cpp
    Reply  Thu Mar 8 22:54:20 2018, Rodrigo Trindade de Menezes, Running drs_example.cpp 
       Reply  Fri May 4 12:11:57 2018, Stefan Ritt, Running drs_example.cpp 
       Reply  Wed Jun 26 15:17:51 2019, Si Xie, Running drs_example.cpp 
    Reply  Mon Mar 19 15:12:02 2018, Stefan Ritt, Running drs_example.cpp 
Message ID: 666     Entry time: Wed Mar 7 22:49:38 2018     Reply to this: 667   674
Author: Rodrigo Trindade de Menezes 
Subject: Running drs_example.cpp 


We have been using the DRS4 evaluation board (S/N 2636) that works with the scope application. However we are trying to run the DRS4 evaluation board remotely by modifying the drs_exam.cpp to acquire and store data continuously.

We compiled the DRS_example.cpp without the wxWidgets but when we try to run the program, it appears to trigger on nonsense.  The program appears to not be sensitive to the trigger threshold (although for very large trigger threshold it gets stuck in a waiting mode).  Is there a way to ensure that the "normal" trigger mode is set?  We are worried that the auto mode is running.  Otherwise, not sure why the program is triggering on nonsense.  By the way, it does not work with the wxWidgets compiled either so we are worried that there is an additional flag that needs to be set. The routine does not appear to conduct a calibration -- is this not necessary?

Another issue that we are having is with the data set stored on the .txt file looks incorrect.  The time channel stops at 200 (but we think it should go up to 1024). In addition, the voltage channel appears to hover around small values near zero (as if triggering on noise).  The output file appears this way even when we change the threshold to much higher values.  It suggests that the trigger threshold is not actually being set? There are events where the output voltage appears to oscillate through huge negative and positive values too.  So not sure what's going on. 



Attachment 1: drs_exam.cpp  4 kB  | Hide | Hide all

  Name:         drs_exam.cpp
  Created by:   Stefan Ritt

  Contents:     Simple example application to read out a DRS4
                evaluation board

  $Id: drs_exam.cpp 21308 2014-04-11 14:50:16Z ritt $


#include <math.h>

#ifdef _MSC_VER

#include <windows.h>

#elif defined(OS_LINUX)

#define O_BINARY 0

#include <unistd.h>
#include <ctype.h>
#include <sys/ioctl.h>
#include <errno.h>

#define DIR_SEPARATOR '/'


#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "strlcpy.h"
#include "DRS.h"


int main()
   int i, j, nBoards;
   DRS *drs;
   DRSBoard *b;
   float time_array[8][1024];
   float wave_array[8][1024];
   FILE  *f;

   /* do initial scan */
   drs = new DRS();

   /* show any found board(s) */
   for (i=0 ; i<drs->GetNumberOfBoards() ; i++) {
      b = drs->GetBoard(i);
      printf("Found DRS4 evaluation board, serial #%d, firmware revision %d\n", 
         b->GetBoardSerialNumber(), b->GetFirmwareVersion());

   /* exit if no board found */
   nBoards = drs->GetNumberOfBoards();
   if (nBoards == 0) {
      printf("No DRS4 evaluation board found\n");
      return 0;

   /* continue working with first board only */
   b = drs->GetBoard(0);

   /* initialize board */

   /* set sampling frequency */
   b->SetFrequency(5, true);

   /* enable transparent mode needed for analog trigger */

   /* set input range to -0.5V ... +0.5V */

   /* use following line to set range to 0..1V */
   /* use following line to turn on the internal 100 MHz clock connected to all channels  */

   /* use following lines to enable hardware trigger on CH1 at 50 mV positive edge */
   if (b->GetBoardType() >= 8) {        // Evaluaiton Board V4&5
      b->EnableTrigger(1, 0);           // enable hardware trigger
      b->SetTriggerSource(1<<0);        // set CH1 as source
   } else if (b->GetBoardType() == 7) { // Evaluation Board V3
      b->EnableTrigger(0, 1);           // lemo off, analog trigger on
      b->SetTriggerSource(0);           // use CH1 as source
   b->SetTriggerLevel(0.3);            // 0.05 V
   printf("Trigger Level CHNN1: 100mV\n");
   b->SetTriggerPolarity(false);        // positive edge
   /* use following lines to set individual trigger elvels */
   //b->SetIndividualTriggerLevel(1, 0.1);
   //b->SetIndividualTriggerLevel(2, 0.2);
   //b->SetIndividualTriggerLevel(3, 0.3);
   //b->SetIndividualTriggerLevel(4, 0.4);
   b->SetTriggerDelayNs(0);             // zero ns trigger delay
   /* use following lines to enable the external trigger */
   //if (b->GetBoardType() == 8) {     // Evaluaiton Board V4
   //   b->EnableTrigger(1, 0);           // enable hardware trigger
   //   b->SetTriggerSource(1<<4);        // set external trigger as source
   //} else {                          // Evaluation Board V3
   //   b->EnableTrigger(1, 0);           // lemo on, analog trigger off
   // }

   /* open file to save waveforms */
   f = fopen("data.txt", "w");
   if (f == NULL) {
      perror("ERROR: Cannot open file \"data.txt\"");
      return 1;
   /* repeat ten times */
   for (j=0 ; j<1000 ; j++) {

      /* start board (activate domino wave) */

      /* wait for trigger */
      printf("Waiting for trigger...");
      while (b->IsBusy());

      /* read all waveforms */
      b->TransferWaves(0, 8);

      /* read time (X) array of first channel in ns */
      b->GetTime(0, 0, b->GetTriggerCell(0), time_array[0]);

      /* decode waveform (Y) array of first channel in mV */
      b->GetWave(0, 0, wave_array[0]);

      /* read time (X) array of second channel in ns
       Note: On the evaluation board input #1 is connected to channel 0 and 1 of
       the DRS chip, input #2 is connected to channel 2 and 3 and so on. So to
       get the input #2 we have to read DRS channel #2, not #1. */
      b->GetTime(0, 2, b->GetTriggerCell(0), time_array[1]);

      /* decode waveform (Y) array of second channel in mV */
      b->GetWave(0, 2, wave_array[1]);

      /* Save waveform: X=time_array[i], Yn=wave_array[n][i] */
      fprintf(f, "Event #%d ----------------------\n  t1[ns]  u1[mV]  t2[ns] u2[mV]\n", j);
      for (i=0 ; i<1024 ; i++)
         fprintf(f, "%7.3f %7.1f %7.3f %7.1f\n", time_array[0][i], wave_array[0][i], time_array[1][i], wave_array[1][i]);

      /* print some progress indication */
      printf("\rEvent #%d read successfully\n", j);

   /* delete DRS object -> close USB connection */
   delete drs;
ELOG V3.1.4-283534d