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ID Date Authorup Subject
  217   Wed Feb 13 16:58:40 2013 Martin PetriskaNonuniform sampling

 Are there any plans to include reconstruction of nonuniform sampling  in DRS4 to get uniformly sampled data?

Im now reading article IEEE Trans on Circ. ans Systems I, Vol.55 No.8 sept. 2008 Reconstruction of Nonuniformly Sampled Bandlimited Signals Usinga Differentiator–Multiplier Cascade by Stefan Tertinek and Christian Vogel

and plan to implement it, but may be somebody has it done before me.

 

  248   Tue May 21 13:32:13 2013 Martin Petriskamac osx 10.6
> Hi,
> 
> I would like to use the DRS4 with my macbook pro running osx 10.6.8.
> I have installed the wxWidgets and the libusb-1.0 libraries and I am using the Linux code vers. 4.0.1. After
> compilation, the following errors come out:
> 
> ld: warning: in musbstd.o, file was built for unsupported file format which is not the architecture being linked
> (i386)
> ld: warning: in mxml.o, file was built for unsupported file format which is not the architecture being linked (i386)
> ....
> ....
> ld: warning: in main.o, file was built for unsupported file format which is not the architecture being linked (i386)
> Undefined symbols:
>   "_main", referenced from:
>       start in crt1.10.6.o
> ld: symbol(s) not found
> collect2: ld returned 1 exit status
> make: *** [drsosc] Error 1
> 
> 
> Do you have any idea on how to solve the problem ?? or maybe do you have a package working with osx 10.6 ? I
> remember to have seen, long time ago, a package that could work with 10.6 (or 10.5 ?), but I cannot find it now
> (but maybe I remember wrong).
> 
> Thanks for any help,
> 
> Enrico

it looks like 64bit vs 32bit problem, you have to compile all libraries for the same architecture. Maybe, make clean to 
remove all precompiled object files .o and recompile it again. Try to compile first that simple example without wxWidgets.

Martin
  321   Thu Jan 9 10:58:19 2014 Martin Petriskav5 software with v4 board calibration

 Hi

Question:

In v4 board, which channel has best calibration ?

Should it be possible to simulate v5 board and read calibration values for v4 board by other method .. for example using external calibration signal source connected to all channels? 

Is it  needed to detach all input signals from EVM board during calibration ?( I see there are switches on channel inputs.)

Some comments: averager.h, averager.cpp are missing in windows v.5 sources (it should be copied from linux sources)

 

PF2014 and thank You for development new EVM 5 and new time precision.

 

Martin

  364   Thu Aug 21 11:03:36 2014 Martin Petriska10GSps on DRS4 Evm with delay cables

 Hi, I read its possible to use channels 2,4,6 to extend 200ns to 400ns (1024bins to 2048).

Is it possible to use same channels to double sampling rate with paralel feeding, one channel delayed by Ts/2, for 5,12GS/s is it cca 3cm delay cable?

 

Martin

  445   Wed Aug 19 15:07:53 2015 Martin PetriskaQtPALS

There is software for DRS4 board and positron lifetime measurement availiable. Still in beta but works. Its usable for measuring time between pulses in two or three channels and histogramming that time. (May be time of flight measurement should be tested too) Project code is here: http://sourceforge.net/projects/qtpals/. More about it is here http://iopscience.iop.org/1742-6596/505/1/012044/. Still tested only with v3 and v4 evaluation board, but should work with new callibration in v5 board too.

  478   Tue Feb 16 11:55:54 2016 Martin PetriskaSaving histogram data

 

Robert Adams wrote:

I would really love to be able to save histogram data, though I have not been able to do this. I could take a screenshot and extract the data from an image, but would prefer to avoid this if there is a simpler way... possibly I have overlooked something obvious? Thanks very much for any advice or tips.

You can use qtpals, there is posibility to save histograms (energy, time diference), only set trigger on channel which you use. https://sourceforge.net/projects/qtpals/files/?source=navbar

  505   Wed Apr 6 09:01:28 2016 Martin PetriskaDRS Oscilloscope freezing after a long run

 

Stefan Ritt wrote:

I tried this night to run the board at a 10 Hz rate with an external pulser, without writing, and it did not freeze after ~14 hours of running on Mac OSX. This night I will try again with writing.

Stefan

Stefan Ritt wrote:

Then it seems that there is some USB communication problem. I heard this also from other people, that the USB data transfer under Windows has sometimes problems. I develop and run the board under Mac OSX, and there the same software runs for days without problem. So I guess it's related to the underlying libusb lib which is used by the DRS oscilloscope, on which I have no influence. So the only advice I can give is to take shorter series of data. Anyhow the board is not considered a full DAQ system, just an "evaluation board" which means one can try the DRS4 chip and play with it. For serious business one should build own electronics with the chip. Anyhow we are currently developping an Ethernet board which allows much faster acquisition rates, so USB will be obsolete some day. Nevertheless I will try to reproduce your problem and see if I can do anything. At what trigger rate does it show up most prominently?

Stefan

Daniel Dribin wrote:

Dear Stefan Ritt,

Yes I use Windows 7, If the DRS Oscilloscope program stays on for a couple of hours without saving the data, the problem will occur. It seems it happens more often when there is data writing and when the rate of events is slow, about 100 events per second, at high rates it almost doesn't happen. Can it be temperature related?

Daniel

Stefan Ritt wrote:

Dear Daniel,

sorry my late reply, I'm pretty busy these days. The behavior you report has not been seen before, but I guess no one tried to take such long runs of data yet. Can you confirm that the problem also occurs without writing data to disk, or is it disk-related? I guess you use it under Windows 7, right?

Stefan

Daniel Dribin wrote:

Dear Stefan Ritt,

I am using a DRS4 v5 to do timing measurements of Positron lifetime. I use the DRS Oscilloscope with triggering on 2 channels when I have a coincidence. Attached is a picture with all the setting that I use. When I use the DRS4 for a long measurements of 5 million events for a couple of hours, the DRS Oscilloscope stops showing any signal .After the first restart of the program I get a strange signal which is at the bottom of the scope range of voltage picture below(in the picture I changed the vertical positions of the channels for better viewing). Only after a couple of DRS Oscilloscope restarts and USB reconnections do I get the results again.

I currently am using another DRS4 v5 and the same situation occurs again although with lower frequency.

What can I do to solve this problem?

thank you very much,

Daniel

 

 

 

 

 

Hi I have also positron annihilation system based on DRS4v4 cards. Its running several weeks, sometimes months, without freezing in windows7 64bit system (Pentium Core Quad 2Ghz, 4GRam).  Problem was when widows was trying to install updates and restarted PC. In beginning I had some problem with memory leak in my application, but it was simple seen in task manager that application memory was rising and was need to find memory leak in application code. Now I remember card was sometimes freezing when room air conditioning with 2kW was starting and high electricity pulses were reason of USB problems, it helped to put air conditioner and PC in different power line input. Hope it help to solve zour problems.

Martin

  592   Wed Apr 5 12:40:16 2017 Martin PetriskaDRS4 eval board v4 coincidence firmware changes for triger for short pulses

I would like to implement fpga firmware changes for DRS4 eval board v4 to put there posibility for standard coincidence (for example to get triger on two short (5ns pulses from Plastic scintilator) in 100ns coincidence window), Similar but more complex was done for eval v.5 boards ( https://forge.physik.rwth-aachen.de/projects/drs4-rwth ) Im beginner in state of FPGA design, but hope it will be not so dificult to implement same functionality in eval4 board. Is there any SVN server with firmware sources for evaluation board? Im litle bit confused with different firmware sources in linux and windows installation packages, For example whose are last eval4 board firmware souces ? (There are some eval4 sources in  5.0.6 files, but not sure if its workable)

May be didnt make same changes already?  

  711   Mon Aug 13 19:44:59 2018 Martin PetriskaLatch delay support

Hi,

https://forge.physik.rwth-aachen.de/projects/drs4-rwth

Not sure about their licensing, but is it possible to add latch delay support to official firmware ?

Best regards

Martin

  714   Mon Sep 3 11:17:26 2018 Martin Petriska"Symmetric spikes" fixed

Hi,

Is it possible to fix it by FPGA changes?  I see readout cycle (proc_drs_reedout) in drs4_eval(4)5_app.vhd, but not sure where to exactly put this three commands. Could you please attach app.vhd file for eval board with example how to fix ?

Regards,

Martin

 

Stefan Ritt wrote:

Good news for all DRS4 users. After many years, I finally understand where the "symmetric spikes" come from and how to fix them.

The "symmetric spikes" are small spikes of 17-18mV, which randomly happen at 1-2 cells. They alwas come in groups of 2 in each channel, symmetric around sampling cell #512. See first attachment.

The reason for the spikes is the previous readout cycle. On each readout cycle, the "read bit" is clocked through all 1024 cells to switch one cell contents to the DRS4 output. At the end of the 1024 cycles, the read bit stays at its last position. The bit is carried by a metal line on the chip, which crosses all 9 channels (second attachment). This bit now influences the sampling cells below the metal line capacitively, so their contents is "pushed up" by a few mV, just like the ROFS offset does. Since the DRS sampling channels are in a snake layout, going 0-512 from left, then 512-1023 back again, the line crosses two cells in each channel, and thus the symmetric spikes.

Previously, there was a software solution for that. In the evaluation board software DRSOsc there is a button "Remove spikes" which tries to fix this in software. Although this works most of the time, it's annoying and not 100% safe. Like when the spike sits on top of a noise signal, it might not be recognized. Fixing this in hardware is however straight forwar. After the readout cycle ends, push the read bit out of the chip:

  • Address the read shift register by applying 1011b to A3:A0
  • Switch SRIN low
  • Apply 1024 clock cycles to SRCLK

This shifts the bit out of the chip, so that the next event is not affected by the read bit. The third attachment show the effect of this. The "clear cycle" increases the readout time a little bit, but depending on the application this might be worth it.

Regards,
Stefan

 

  716   Thu Sep 13 18:09:13 2018 Martin Petriska"Symmetric spikes" fixed

Ok, so I made it ... and Yes it works :), 

https://youtu.be/0noy4CoFoh8 

here is changed part in drs4_eval4_app.vhd

               
        when done =>
          drs_readout_state    <= spikeoff;
          drs_stat_busy        <= '0';
          drs_dpram_we1        <= '0';
          drs_write_set        <= '1';   -- set drs_write_ff in proc_drs_write
                                         -- to keep chip "warm"

 -- spike fix ELOG 697        
 
          when spikeoff => 
            o_drs_addr       <= "1011"; -- Address the read shift register by applying 1011b to A3:A0
            o_drs_srin       <= '0'; -- Switch SRIN low             
             drs_readout_state                 <= spikecycle;
             -- Apply 1024 clock cycles to SRCLK     
             drs_sr_count         <= 0;

          when spikecycle =>      
             drs_sr_count         <= drs_sr_count + 1;
             o_drs_srclk          <= not o_drs_srclk;
             if (drs_sr_count = 1024) then
                drs_readout_state <= idle;
             end if;      


        -- set-up of configuration register        

Stefan Ritt wrote:

Yes it's possible, but I have to find time for that. The software of the evaluation board takes care of the spikes ("remove spikes"), so I thought it's not so urgent to fix that in the FPGA (which takes me some time).

Stefan

Martin Petriska wrote:

Hi,

Is it possible to fix it by FPGA changes?  I see readout cycle (proc_drs_reedout) in drs4_eval(4)5_app.vhd, but not sure where to exactly put this three commands. Could you please attach app.vhd file for eval board with example how to fix ?

Regards,

Martin

 

Stefan Ritt wrote:

Good news for all DRS4 users. After many years, I finally understand where the "symmetric spikes" come from and how to fix them.

The "symmetric spikes" are small spikes of 17-18mV, which randomly happen at 1-2 cells. They alwas come in groups of 2 in each channel, symmetric around sampling cell #512. See first attachment.

The reason for the spikes is the previous readout cycle. On each readout cycle, the "read bit" is clocked through all 1024 cells to switch one cell contents to the DRS4 output. At the end of the 1024 cycles, the read bit stays at its last position. The bit is carried by a metal line on the chip, which crosses all 9 channels (second attachment). This bit now influences the sampling cells below the metal line capacitively, so their contents is "pushed up" by a few mV, just like the ROFS offset does. Since the DRS sampling channels are in a snake layout, going 0-512 from left, then 512-1023 back again, the line crosses two cells in each channel, and thus the symmetric spikes.

Previously, there was a software solution for that. In the evaluation board software DRSOsc there is a button "Remove spikes" which tries to fix this in software. Although this works most of the time, it's annoying and not 100% safe. Like when the spike sits on top of a noise signal, it might not be recognized. Fixing this in hardware is however straight forwar. After the readout cycle ends, push the read bit out of the chip:

  • Address the read shift register by applying 1011b to A3:A0
  • Switch SRIN low
  • Apply 1024 clock cycles to SRCLK

This shifts the bit out of the chip, so that the next event is not affected by the read bit. The third attachment show the effect of this. The "clear cycle" increases the readout time a little bit, but depending on the application this might be worth it.

Regards,
Stefan

 

 

 

  809   Thu Feb 25 17:56:39 2021 Matthias PlumDRS spike removal for multiple waveforms

Hi,

Is there a way that someone can help me and my student to enable RemoveSymmetricSpikes function in the drs_exam.cpp? We are not 100% sure how to call the function if you want to read out four waveforms.

Cheers,

Matthias

  173   Wed Aug 1 17:42:32 2012 Mayank S. RajguruCalculation of loop filter parameters (R,C1and C1) for 1 GHz

 Hi,

we are planning to use the DRS4 in our board for 1 GHz sampling and digitization.

I have seen in the data sheet that "For the PLL to work, an external loop filter is required. This filter ensures quick locking and stable operation at the desired sampling frequency".

What formula do you use to calculate the values of R, C1 and C2?

Can we use the same given value for different frequencies?

Thanks,

Mayak

  829   Wed Jul 14 14:55:09 2021 Mehrpad MonajemC code to read the 4 channel with external trigger

Hi there,

Recently I bought a 5GSPS evaluation board with 2048 sampling points.
I want to read 4 inputs of the evaluation bord ar 5 GSPS or 2.5GSP and use an external trigger.
I've checked your website and download drs-5.0.5 which contains the source code in C. It seems that the file drs_exam.cpp can do what I am looking for.
So far I could make and compile the project in Linux Ubuntu, but I couldn't compile it in Windows 10.  I've used Cygwin64 to compile the project in windows 10.

I have the following questions:

1- Since I only need to compile the drs_exam.cpp file, could please help me with how can I compile it directly(without making the entire project). Or tell me which version of Wxwidget and libusb I have to install.

2- If you have any sample code that can read 4 inputs with an external trigger, please tell me where can I find it.

In the end, I want to write a wrapper on this C file(which returns digitized data) and run it from my python program. Thank you in advance.
Best regards,
Mehrpad

 

  831   Tue Aug 10 13:57:09 2021 Mehrpad MonajemC code to read the 4 channel with external trigger

Thank you for the reply.

In the version that I have, I cannot find drs_exam_2048.cpp file. Could you please send me the link to download the software folder, which contain this file.

Best,

Mehrpad

Stefan Ritt wrote:

Sorry the late reply, I was on vacation. 

Here are some answers:

1. I'm sorry I can't help much here, since I currently don't have a Windows 10 computer here to compile any code. I moved now completely to MacOSX, being very similar to Linux. I'm not allowed to run a Windows 7 computer any more for security reasons. Last time this worked for me was with Wxwidget version 3.0 and libusb 1.0, but I guess libusb is not critical so you can use a newer version. If you just compile drs_exam.cpp, you don't need any Wxwidget library. That one is only used for the oscilloscope program.

2. The program drs_exam_2048.cpp is meant to read channels in 2048-bin mode.

3. To adjust the delay between the trigger and the readout, use the function b->SetTriggerDelayNs(xxx)

Best,
Stefan

Mehrpad Monajem wrote:

Hi there,

Recently I bought a 5GSPS evaluation board with 2048 sampling points.
I want to read 4 inputs of the evaluation bord ar 5 GSPS or 2.5GSP and use an external trigger.
I've checked your website and download drs-5.0.5 which contains the source code in C. It seems that the file drs_exam.cpp can do what I am looking for.
So far I could make and compile the project in Linux Ubuntu, but I couldn't compile it in Windows 10.  I've used Cygwin64 to compile the project in windows 10.

I have the following questions:

1- Since I only need to compile the drs_exam.cpp file, could please help me with how can I compile it directly(without making the entire project). Or tell me which version of Wxwidget and libusb I have to install.

2- If you have any sample code that can read 4 inputs with an external trigger, please tell me where can I find it.

In the end, I want to write a wrapper on this C file(which returns digitized data) and run it from my python program. Thank you in advance.
Best regards,
Mehrpad

 

 

 

  Draft   Wed Oct 13 12:14:04 2021 Mehrpad Monajem 

Hi there,

I want to use the "drs_exam.cpp" file for my project. The "drs_exam.cpp" file
Best regards,
Mehrpad

  528   Sun Jun 12 08:45:52 2016 Michaelproblems of DRS4

Hi

I want to use DRS4 to digitize 16 channels of signals. The width of signal is about 20 ns, with frequency of 50Hz. The time differences between these 16 signals are not constant, arranging from 3us to 0. I am confused about this in some aspects.

  1. Can I use SIMULTANEOUS WRITINT AND READING to realize this? I saw the VHDL program, and if I understand it correctly, it did not work at this state.
  2. Or sampling at 1GSPS, using CASCADING OF CHANNELS, I can sample signal at most 4us or 8us, then digitizing all signals of one chip. Have you tested 4 or more channels cascading before?

Besides, any advice will be helpful!

Thank you.

  Draft   Sun Jun 12 08:49:54 2016 Michaelproblems of DRS4

Hi

I want to use DRS4 to digitize 16 channels of signals. The width of signal is about 20 ns, with frequency of 50Hz. The time differences between these 16 signals are not constant, arranging from 3us to 0. I am confused about this in some aspects.

  1. Can I use SIMULTANEOUS WRITINT AND READING to realize this? I saw the VHDL program, and if I understand it correctly, it did not work at this state.
  2. Or sampling at 1GSPS, using CASCADING OF CHANNELS, I can sample signal at most 4us or 8us, then digitizing all signals of one chip. Have you tested 4 or more channels cascading before?

Besides, any advice will be helpful!

Thank you.

  431   Tue Jun 16 20:45:54 2015 Michael BuadelkDRS4 Evaluation Board Osc Application

Hi, I have a DRS4 v5 evaluation board and I have a novice question about the oscilliscop application. When I connect it to a photo-detector (silicon photo-multiplier to be exact), the signal appears only on one half of the screen, and I cannot change it to be full screen, and pulse to be centered. I tried changing delay time and played around with the settings of the applicaton but no success. I'd apprecite if someone help me on this, probably very simple, problem.

  138   Fri Dec 9 17:45:48 2011 Michael BŁkerFixes to DOScreen.cpp for recent built on linux
> I was just building version 3.1.0 and ran into some problems in DOScreen.cpp.  Basically the conversions from
> char* to wxString were generating "ambiguous overload" errors (in gcc 4.4.3, wx-2.8)
> 
> The simple fix is given in  the following diff output.

Today, I ran into the same problem and was happy to find your fix. I've incorporated it into a unified diff file,
that can easily be applied with the patch program by saving it into a file ('drsosc-3.1.0-wxfix.patch', say), and
in the drs-3.1.0 directory running:

patch -1 < drsosc-3.1.0-wxfix.patch

This is the file:

--- src/DOScreen.cpp.orig	2011-12-09 15:49:48.682201902 +0100
+++ src/DOScreen.cpp		2011-12-09 15:51:45.666000111 +0100
@@ -234,7 +234,7 @@ void DOScreen::DrawWaveform(wxDC& dc, wx
 
    // display optional debug messages
    if (*m_frame->GetOsci()->GetDebugMsg()) {
-      wxst = m_frame->GetOsci()->GetDebugMsg();
+      wxst = wxString(m_frame->GetOsci()->GetDebugMsg(),wxConvUTF8);
       dc.SetPen(wxPen(*wxLIGHT_GREY, 1, wxSOLID));
       dc.SetBrush(*wxGREEN);
       dc.SetTextForeground(*wxBLACK);
@@ -243,7 +243,7 @@ void DOScreen::DrawWaveform(wxDC& dc, wx
       dc.DrawText(wxst, m_x1+4, m_y1+2);
    }
    if (m_debugMsg[0]) {
-      wxst = m_debugMsg;
+      wxst = wxString(m_debugMsg,wxConvUTF8);
       dc.SetPen(wxPen(*wxLIGHT_GREY, 1, wxSOLID));
       dc.SetBrush(*wxGREEN);
       dc.SetTextForeground(*wxBLACK);
@@ -474,9 +474,9 @@ void DOScreen::DrawWaveform(wxDC& dc, wx
    if (m_osci->GetNumberOfBoards() && m_osci->IsIdle()) {
       dc.SetTextForeground(*wxGREEN);
       if (m_osci->GetTriggerMode() == TM_AUTO)
-         wxst = "AUTO";
+         wxst = wxString("AUTO",wxConvUTF8);
       else
-         wxst = "TRIG?";
+         wxst = wxString("TRIG?",wxConvUTF8);
       dc.GetTextExtent(wxst, &w, &h);
       dc.DrawText(wxst, m_x2 - w - 2, m_y1 + 1);
    }
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