ELOG DRS4 Forum

Hi,

I'm currently working on a little DAQ system with four DRS evaluation boards. Do i need to apply any specific settings when using the clock in/out connectors for synchronization? I do not see anything like that in the drs_exam_multi example.

Any help would be greatly appreciated!

Best,

Simon

387

Wed Oct 15 10:52:58 2014

Simon Weingarten wrote:

Hi,

Any help would be greatly appreciated!

Best,

Simon

Right, I did not yet put any code there. What you need on all slave boards is

b->SetRefclk(true);

b->SetFrequency(...);

Set SetFrequency() is needed to restart the boards with the external clock.

This works of course only if you have the clock signals connected as written in the manual. If not, the boards won't work after you switch the reference clock.

Best regards,
Stefan

388

Wed Oct 15 11:34:43 2014

Simon Weingarten

Stefan Ritt wrote:

Simon Weingarten wrote:

Hi,

Any help would be greatly appreciated!

Best,

Simon

Right, I did not yet put any code there. What you need on all slave boards is

b->SetRefclk(true);

b->SetFrequency(...);

Set SetFrequency() is needed to restart the boards with the external clock.

This works of course only if you have the clock signals connected as written in the manual. If not, the boards won't work after you switch the reference clock.

Best regards,
Stefan

Thank you so much for the fast reply! I'll give it a try.

Best regards,

Simon

389

Wed Oct 15 12:15:58 2014

Here is the full version of the program with clock daisy-chaining. Before switching to the external clock, it checks if the clock really is there (by reading an internal scaler), and only then enables it. Note that the code also works without clock daisy-chaining. But without clock daisy-chaining your have some 400 ps time resolution between boards, and with clock daisy-chaining you get some 60 ps.

Attachment 1: drs_exam_multi.cpp

/********************************************************************\

  Name:         drs_exam_multi.cpp
  Created by:   Stefan Ritt

  Contents:     Simple example application to read out a several
                DRS4 evaluation board in daisy-chain mode

  $Id: drs_exam_multi.cpp 21509 2014-10-15 10:11:36Z 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 '/'

#endif

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

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

/*------------------------------------------------------------------*/

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

   /* do initial scan, sort boards accordning to their serial numbers */
   drs = new DRS();
   drs->SortBoards();

   /* 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());
      if (b->GetBoardType() < 8) {
         printf("Found pre-V4 board, aborting\n");
         return 0;
      }
   }
   
   /* exit if no board found */
   if (drs->GetNumberOfBoards() == 0) {
      printf("No DRS4 evaluation board found\n");
      return 0;
   }

   /* exit if only one board found */
   if (drs->GetNumberOfBoards() == 1) {
      printf("Only one DRS4 evaluation board found, please use drs_exam program\n");
      return 0;
   }
   
   /* use first board with highest serial number as the master board */
   mb = drs->GetBoard(0);
   
   /* common configuration for all boards */
   for (i=0 ; i<drs->GetNumberOfBoards() ; i++) {
      b = drs->GetBoard(i);
      
      /* initialize board */
      b->Init();
      
      /* select external reference clock for slave modules */
      /* NOTE: this only works if the clock chain is connected */
      if (i > 0) {
         if (b->GetFirmwareVersion() >= 21260) { // this only works with recent firmware versions
            if (b->GetScaler(5) > 300000)        // check if external clock is connected
               b->SetRefclk(true);               // switch to external reference clock
         }
      }
      
      /* set sampling frequency */
      b->SetFrequency(5, true);
      
      /* set input range to -0.5V ... +0.5V */
      b->SetInputRange(0);

      /* enable hardware trigger */
      b->EnableTrigger(1, 0);
      
      if (i == 0) {
         /* master board: enable hardware trigger on CH1 at 50 mV positive edge */
         b->SetTranspMode(1);
         b->SetTriggerSource(1<<0);        // set CH1 as source
         b->SetTriggerLevel(0.05);         // 50 mV
         b->SetTriggerPolarity(false);     // positive edge
         b->SetTriggerDelayNs(0);          // zero ns trigger delay
      } else {
         /* slave boards: enable hardware trigger on Trigger IN */
         b->SetTriggerSource(1<<4);        // set Trigger IN as source
         b->SetTriggerPolarity(false);     // positive edge
      }
   }

   /* 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 (i=0 ; i<10 ; i++) {

      /* start boards (activate domino wave), master is last */
      for (j=drs->GetNumberOfBoards()-1 ; j>=0 ; j--)
         drs->GetBoard(j)->StartDomino();

      /* wait for trigger on master board */
      printf("Waiting for trigger...");
      fflush(stdout);
      while (mb->IsBusy());

      fprintf(f, "Event #%d =====================================================\n", j);

      for (j=0 ; j<drs->GetNumberOfBoards() ; j++) {
         b = drs->GetBoard(j);
         if (b->IsBusy()) {
            i--; /* skip that event, must be some fake trigger */
            break;
         }
         
         /* read all waveforms from all boards */
         b->TransferWaves(0, 8);
         
         for (k=0 ; k<4 ; k++) {
            /* read time (X) array in ns */
            b->GetTime(0, k*2, b->GetTriggerCell(0), time_array[k]);

            /* decode waveform (Y) arrays in mV */
            b->GetWave(0, k*2, wave_array[k]);
         }

         /* Save waveform: X=time_array[i], Channel_n=wave_array[n][i] */
         fprintf(f, "Board #%d ---------------------------------------------------\n t1[ns]  u1[mV]  t2[ns]  u2[mV]  t3[ns]  u3[mV]  t4[ns]  u4[mV]\n", b->GetBoardSerialNumber());
         for (k=0 ; k<1024 ; k++)
            fprintf(f, "%7.3f %7.1f %7.3f %7.1f %7.3f %7.1f %7.3f %7.1f\n",
                    time_array[0][k], wave_array[0][k],
                    time_array[1][k], wave_array[1][k],
                    time_array[2][k], wave_array[2][k],
                    time_array[3][k], wave_array[3][k]);
      }

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

   fclose(f);
   
   printf("Program finished.\n");

   /* delete DRS object -> close USB connection */
   delete drs;
}

403

Fri Apr 17 10:07:38 2015

Simon Weingarten

Hi Stefan,

do you know how these numbers (400ps and 60ps) scale with the sampling rate? The manual says they are for 5GS/s, do they change with slower sampling?

Thanks and best regards,

Simon

Stefan Ritt wrote:

404

Mon Apr 20 13:08:24 2015

The resolution coming from the sampling rate goes into these numbers, but just marginally. At 5 GSPS, you get a few ps reolution, while at 1 GSPS, you get like 15 ps. If you convolve 15 ps with 400 ps, you get 400.3 ps, which is not significantly worse than 400 ps.

Simon Weingarten wrote:

Hi Stefan,

do you know how these numbers (400ps and 60ps) scale with the sampling rate? The manual says they are for 5GS/s, do they change with slower sampling?

Thanks and best regards,

Simon

Stefan Ritt wrote:

222

Wed Feb 27 13:47:32 2013

Georg Winner

Chip Test - Cell Error

When starting Chip Test in DRS Command Line Interface, I receive the following message:

Cell error on channel 1, cell 5: -154.4 mV instead 0 mV

Chip Error!

What does this mean? The maximal peak-to-peak Amplitude given to channel was for a short time 10V.

The graphical interface shows no artefacts when using channel 1.

227

Wed Mar 6 13:08:03 2013

Channel offsets in GetTime()

Chip Test - Cell Error

Georg Winner wrote:

When starting Chip Test in DRS Command Line Interface, I receive the following message:

Cell error on channel 1, cell 5: -154.4 mV instead 0 mV

Chip Error!

What does this mean? The maximal peak-to-peak Amplitude given to channel was for a short time 10V.

The graphical interface shows no artefacts when using channel 1.

The "Chip Test" command is made for a special test board we use for chip testing. This command will not work with the evaluation board, since only four of the 8 DRS channels are connected there. So just ignore it and verify the board functionality by looking at the graphical interface.

/Stefan

563

Fri Nov 18 05:52:45 2016

Kurtis Nishimura

Hello,

I have a question about the GetTime() method in DRS.cpp. I understand how the DT values are applied for all channels, and I also understand from the evaluation board manual that the timing of each channel is synchronized at sample 0, so samples should really be aligned from channel-to-channel relative to sample 0.

However, DRS.cpp has the following snippet in DrsBoard::GetTime():

if (channelIndex > 0) { // correct all channels to channel 0 (Daniel's method) iend = tc >= 700 ? 700+1024 : 700; for (i=tc,gt0=0 ; i<iend ; i++) gt0 += fCellDT[chipIndex][0][i % 1024]; for (i=tc,gt=0 ; i<iend ; i++) gt += fCellDT[chipIndex][channelIndex][i % 1024]; for (i=0 ; i<fChannelDepth ; i++) time[i] += (float)(gt0 - gt); }

I can see what this is calculating and applying such an offset, but I don't understand why things seem to be referenced to sample 700. Is there a particular reason why sample 700 is chosen here? This does not seem like a straightforward application of the attached instructions from the evaluation board user's manual.

Any insight would be much appreciated!

Thanks so much,

-Kurtis

Attachment 1: offsetInstructions.png

565

Mon Nov 21 14:13:32 2016

Channel offsets in GetTime()

Cell 700 is arbitrary. You can choose any cell to align the channels to each other. The only requirement is that it's always the same cell for each event. Historically, Daniel chose cell #700 more or less arbitrary, but later we found out that this works with any cell. So for the publication we went with cell #0 (and that's why we have t_ch,0 in the paper), but cell #700 was left in the code because of lazyness. Feel free to replace 700 with any other number and you should get the same result. In a newer version of the software I use

// align cell#0 of all channels float t1 = time[0][(1024-tc) % 1024]; for (int ch=1 ; ch<8 ; ch++) { float t2 = time[ch][(1024-tc) % 1024]; float dt = t1 - t2;
for (int i=0 ; i<1024 ; i++) time[ch][i] += dt; }

which is also a bit simpler. So time[ch] contains already the integrated time array (like 0.2 ns, 0.4 ns, 0.6 ns if at 5 GSPS, not the delta_t values as in the DRS.cpp code). Since the readout starts with cell # tc, the cell time[channel][1024-tc] is the physical cell #0 of the chip. The code makes sure that cell #0 in all 8 channels has the same time value.

Best regards,
Stefan

Kurtis Nishimura wrote:

Hello,

However, DRS.cpp has the following snippet in DrsBoard::GetTime():

if (channelIndex > 0) { // correct all channels to channel 0 (Daniel's method) iend = tc >= 700 ? 700+1024 : 700; for (i=tc,gt0=0 ; i<iend ; i++) gt0 += fCellDT[chipIndex][0][i % 1024]; for (i=tc,gt=0 ; i<iend ; i++) gt += fCellDT[chipIndex][channelIndex][i % 1024]; for (i=0 ; i<fChannelDepth ; i++) time[i] += (float)(gt0 - gt); }

Any insight would be much appreciated!

Thanks so much,

-Kurtis

895

Sat Oct 22 13:24:20 2022

Phan Van Chuan

Channel Cascading Option in the 2048-bin

Dear Stefan,
We are using DRS4 evaluation board version 5.1 and firmware version 30000 (as the picture attached). Now, I am in need one channel with length 2048 bin. However, I can't find the resistors R99, ... ,R106 on the hardware of evaluation board; it seems my DRS4 evaluation board doesn't use 2048 bins per channel.
Our question is, can we repair this hardware to read 2048 bins/channel? if that is possible please let me know what to add on hardware/software of DRS4 evaluation.
Best regards.
Phan Van Chuan.

Attachment 1: DRS4V51.png

896

Mon Oct 24 12:50:24 2022

Channel Cascading Option in the 2048-bin

The board is delivered in one or the other mode and not meant to be changed by the user, since this requires very delicate soldering which is not easy. If you try anyhow, you loose the quarantee. You can send the board back to the manufacturer for the modification, but this costs quite some moeny.

Best regards,
Stefan

Phan Van Chuan wrote:

795

Mon Aug 31 16:44:12 2020

Hans Steiger

Channel Cascading

Dear All,

I have a board with Channel Cascading Option. I have the problem, that it seems to be impossible to run all 4 Channels simultaneously for digitizing pulses. I can just run even or odd channels but not even and odd ones? If I run in combined option, My question: If a board comes with this combined option, is it still usable as a 4Ch Digitizer but with 1024bin traces?

All the best,

Hans

796

Mon Aug 31 17:17:30 2020

Channel Cascading

If you have a board with cascading option, it should show the "combined" option in the 2048-bin option enabled (not grayed), as in the attached screen shot. If the 2048-bin option is all greyed out, the system does not recognize the cascading option. If your board has a sticker "2048 bin" and you still see the 2048-bin option greyed out, it might mean that a resistor on that board has been forgotten. If you do not see the "2048 bin" sticker on your board, you might not have a board with cascading option. So please check that. If the resistor is really missing, you can send us the board and we will add it.

Stefan

Hans Steiger wrote:

Dear All,

All the best,

Hans

Attachment 1: Screenshot_2020-08-31_at_16.52.28_.png

302

Thu Nov 14 11:39:06 2013

Schablo

Hello, I want use cascading of channels for 2048 cell - SetChannelConfig(0,8,4), but i can't understand how . Please, help me. Where i can dowload 2048_mode.ppt. (I found information about this file in DRS.cpp (3445 line "/ combine two halfs correctly, see 2048_mode.ppt")

Best regards,

Schablo Kostya

303

Thu Nov 14 12:51:56 2013

Schablo wrote:

Best regards,

Schablo Kostya

You have to combine two channels into one, and depending on where the domino wave stopped, things get a bit complicated. I attach 2048_mode.ppt for your reference, but am not sure if this will really help.

/Stefan

Attachment 1: 2048_mode.pdf

311

Thu Nov 21 14:35:57 2013

Schablo

Stefan Ritt wrote:

Schablo wrote:

Best regards,

Schablo Kostya

/Stefan

Sorry for my question.

I'm trying change "drs_exam.cpp" for read 2048 cell.

I'm using SetChannnelConfig(0,8,4) and this code in "drs_exam.cpp" :

...

float arrX[2048];

float arrY[2048];

....

b->GetTime(0, b->GetTriggerCell(0), arrX);

b->GetWave(0, 0, arr.Y);

....

Return 2048 values in arrX[2048] - correct values, but in arrY[2048] - not correct values.

I can't understand what values return "GetWave" function. Please, say me how make, that GetWave function return correct values. " not - correct values "(i mean that i give signal in drs bord and values not true.)

Best regards,

Schablo Kostya

312

Thu Nov 21 14:45:56 2013

Cannot trigger on pulses, have to trigger on undershoot

Schablo wrote:

Stefan Ritt wrote:

Schablo wrote:

Best regards,

Schablo Kostya

/Stefan

Sorry for my question.

I'm trying change "drs_exam.cpp" for read 2048 cell.

I'm using SetChannnelConfig(0,8,4) and this code in "drs_exam.cpp" :

...

float arrX[2048];

float arrY[2048];

....

b->GetTime(0, b->GetTriggerCell(0), arrX);

b->GetWave(0, 0, arr.Y);

....

Return 2048 values in arrX[2048] - correct values, but in arrY[2048] - not correct values.

Best regards,

Schablo Kostya

The evaluation board V4 does not support cascading by default. You have to connect each input to two channels, which can in principle be made by soldering some zero Ohm resistors on the board, but these are tiny parts and not everybody can do it. Note that the 2048 cell mode is an option when ordering the board. So first make sure that you can modify the board before trying to run the software.

862

Sat Feb 12 13:06:56 2022

Matias Senger

I am using the DRS4 board trying to measure pulses produced by an LGAD. I have no prior experience with this board, have just installed the `drsosc` application and am exploring. I am experiencing some strange trigger behavior. Consider the following screenshot:

Here nothing is strange, the board is triggering on the undershoot and it is working fine, I can trigger on rising/falling edge, different levels, etc.

Now, the strange thing is that if I pull the trigger up to trigger on the pulse itself it stops triggering:

I have tried many different setups for the trigger (rising, falling edge, different levels, etc) and nothing works. In the undershoot, everything works.

I have tried with the internal test signal and it works fine:

What could be the problem?

I have run the voltage and time calibrations as suggested in the manual.

864

Tue Feb 15 12:02:29 2022