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  404   Mon Apr 20 13:08:24 2015 Stefan RittClock settings in daisy chain DAQ

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:

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.

 

 

  222   Wed Feb 27 13:47:32 2013 Georg WinnerChip 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 Stefan RittChip 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 NishimuraChannel offsets in GetTime()

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

  565   Mon Nov 21 14:13:32 2016 Stefan RittChannel 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,

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

 

  795   Mon Aug 31 16:44:12 2020 Hans SteigerChannel 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 Stefan RittChannel 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,

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

 

  302   Thu Nov 14 11:39:06 2013 SchabloCascading of channels

 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 Stefan RittCascading of channels

Schablo wrote:

 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 

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 

  311   Thu Nov 21 14:35:57 2013 SchabloCascading of channels

Stefan Ritt wrote:

Schablo wrote:

 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 

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 

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 Stefan RittCascading of channels

Schablo wrote:

Stefan Ritt wrote:

Schablo wrote:

 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 

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 

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 

 

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. 

  350   Thu May 29 04:22:43 2014 Toshihiro NonakaCalibrationWaveform

I'm writing the drs_exam.cpp to use multi-boards(v3, firmware:4.0.0), and taking data succeeded. But I have several questions about function written in DRS.cpp.

 

  1. I wrote following code in drs_exam.cpp to set input range -0.4~0.6

                                     b1->SetInputRange(0.1);

            And the 100mV offset appeared(I attached a picture). I think this is due to the voltage calibration isn't done.(Calibrated to -0.5~0.5mV in DRS Oscilloscope)

            If so, could you show me a simple usage of "CalibrationWaveform()" function in DRS.cpp? (or other function?)

 

       2. Although this question might be the almost same with above, is there any way to execute voltage and timing calibration in drs_exam.cpp?

           Now I start DAQ by executing drs_exam.cpp after I execute voltage and timing calibration to each board by DRS Oscilloscope program.

 

      3. Which command is right to use external trigger?

                                   b1->SetTriggerSource(4);   or  b1->SetTriggerSource(1<<4);

 

Best regards,

Toshihiro Nonaka

  355   Thu Jun 12 17:16:13 2014 Stefan RittCalibrationWaveform

Toshihiro Nonaka wrote:

I'm writing the drs_exam.cpp to use multi-boards(v3, firmware:4.0.0), and taking data succeeded. But I have several questions about function written in DRS.cpp.

 

  1. I wrote following code in drs_exam.cpp to set input range -0.4~0.6

                                     b1->SetInputRange(0.1);

            And the 100mV offset appeared(I attached a picture). I think this is due to the voltage calibration isn't done.(Calibrated to -0.5~0.5mV in DRS Oscilloscope)

            If so, could you show me a simple usage of "CalibrationWaveform()" function in DRS.cpp? (or other function?)

 

       2. Although this question might be the almost same with above, is there any way to execute voltage and timing calibration in drs_exam.cpp?

           Now I start DAQ by executing drs_exam.cpp after I execute voltage and timing calibration to each board by DRS Oscilloscope program.

 

      3. Which command is right to use external trigger?

                                   b1->SetTriggerSource(4);   or  b1->SetTriggerSource(1<<4);

 

Best regards,

Toshihiro Nonaka

1. b->CalibrateVolt(NULL);

2. see 1.

3. For the V3 boards use b->SetTriggerSource(4), for V4 and V5 boards, use b->SetTriggerSource(1<<4). I had to change that because from V4 on we can have logical combinations between channels (like channel 1 AND channel 2).

Best regards,

Stefan 

  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

  174   Mon Aug 6 02:44:00 2012 Stefan RittCalculation of loop filter parameters (R,C1and C1) for 1 GHz

Mayank S. Rajguru wrote:

 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

I never worked out an exact formula for the parameters. It also depends if you want a fast locking time, or a low phase jitter of the PLL. A good starting point are the values from the evaluation board:

R = 130 Ohm

C1 = 4.7 nF

C2 = 1 uF

They should work from 800 MHz to 5 GHz.

- Stefan 

  557   Thu Nov 10 04:41:24 2016 Abhishek RajputBreak Statements in DRS4 Binary to ROOT Macro

Hello,

I recently modified the binary to ROOT convertor written by Stefan (https://midas.psi.ch/elogs/DRS4+Forum/361) so it can decode data taken with any channel or set of channels  on the DRS4. In the process of testing this modifed version for data taken on all 4 channels, I encountered problems with decoding some of the event data. More specifically, upon hitting a certain event in some channel, the histograms for that channel would no longer be filled and the histograms for subsequent channels would not be filled with any event at all. 

After considerable bug hunting, I discovered the source of this problem was due to the break statement in the following code extract from the ROOT to binary macro:

 for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < 1)
         break;

For some events apparently, the event header fails to be read properly (fread line returns 0 in this case). Moreover, when I used the feof and ferror functions on a particular file I was testing, the feof function returned a value of 1.

So my questions deal with two scenarios.

Firstly, in the event of an fread error, is a break statement is necessary? Is it not possible to skip the voltage data for those events whose event header fails to be read properly? Or is it the case that when some "corrupted" event header is encountered, all waveform data subsequent to that event is likewise corrupted? If the former is the case, is it advisable to replace the break condition with an fseek line that advances the position indicator of the stream by an additional 2052*n_channels + 32 bytes (in accordance with the binary file specifications of page 25 on the DRS4 manual) so that the next set of voltage data can be read? 

Secondly, in the case of an end of file error, does there exist any possible solution? Or is such an error an indication of a faulty drs4 channel or corrupted binary file? 

Any help with the aforementioned issues would be greatly appreciated.

 

Abhishek

 

  558   Thu Nov 10 09:56:04 2016 Stefan RittBreak Statements in DRS4 Binary to ROOT Macro

Hi,

fread() returns the number of bytes read and zero (I believe) if there is an end of file. So this break statement is a simple end-of-file test. There might be other erros such as hard disk failures, but these are extremely rare. 

If course the file should not end in the middle of an event header. If it does, it means the file is corrupted and truncated, and we should not continue to read that file, that's why there is the break. The internal file is just a series of bytes, it does not know about the event header, so there will be no "error" if we have for example a missing event header but a voltage array. To be correct, the code should actually read

for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < sizeof(eh))
         break;

Hope this helps,

Stefan

Abhishek Rajput wrote:

Hello,

I recently modified the binary to ROOT convertor written by Stefan (https://midas.psi.ch/elogs/DRS4+Forum/361) so it can decode data taken with any channel or set of channels  on the DRS4. In the process of testing this modifed version for data taken on all 4 channels, I encountered problems with decoding some of the event data. More specifically, upon hitting a certain event in some channel, the histograms for that channel would no longer be filled and the histograms for subsequent channels would not be filled with any event at all. 

After considerable bug hunting, I discovered the source of this problem was due to the break statement in the following code extract from the ROOT to binary macro:

 for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < 1)
         break;

For some events apparently, the event header fails to be read properly (fread line returns 0 in this case). Moreover, when I used the feof and ferror functions on a particular file I was testing, the feof function returned a value of 1.

So my questions deal with two scenarios.

Firstly, in the event of an fread error, is a break statement is necessary? Is it not possible to skip the voltage data for those events whose event header fails to be read properly? Or is it the case that when some "corrupted" event header is encountered, all waveform data subsequent to that event is likewise corrupted? If the former is the case, is it advisable to replace the break condition with an fseek line that advances the position indicator of the stream by an additional 2052*n_channels + 32 bytes (in accordance with the binary file specifications of page 25 on the DRS4 manual) so that the next set of voltage data can be read? 

Secondly, in the case of an end of file error, does there exist any possible solution? Or is such an error an indication of a faulty drs4 channel or corrupted binary file? 

Any help with the aforementioned issues would be greatly appreciated.

 

Abhishek

 

 

  560   Thu Nov 10 19:24:52 2016 Abhishek RajputBreak Statements in DRS4 Binary to ROOT Macro

Hello,

I am wondering why the code should be changed to i < sizeof(eh), since doesn't fread(&eh,sizeof(eh),1,f) return 1 in this scenario? I've confirmed with a cout statement that this is the case, so this break condition will therefore always trigger as sizeof(eh) is 32 bytes. 

Either way, I believe I figured out my problem. In my revised version of your code, I had two nested loops, the outer one being a loop over the channels and the inner one being a loop over the events. However, I really should have been doing the reverse considering the binary structure of the file.  Otherwise, the end of the file will be reached for only a single iteration of the channel loop if I choose to loop through all the events in the data file.

Once I modified the code to have the outer loop be over all the events and the inner one be over all the channels, I no longer suffered from breaks in the loops. 

Many thanks for your assistance. 

Abhishek 

Stefan Ritt wrote:

Hi,

fread() returns the number of bytes read and zero (I believe) if there is an end of file. So this break statement is a simple end-of-file test. There might be other erros such as hard disk failures, but these are extremely rare. 

If course the file should not end in the middle of an event header. If it does, it means the file is corrupted and truncated, and we should not continue to read that file, that's why there is the break. The internal file is just a series of bytes, it does not know about the event header, so there will be no "error" if we have for example a missing event header but a voltage array. To be correct, the code should actually read

for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < sizeof(eh))
         break;

Hope this helps,

Stefan

Abhishek Rajput wrote:

Hello,

I recently modified the binary to ROOT convertor written by Stefan (https://midas.psi.ch/elogs/DRS4+Forum/361) so it can decode data taken with any channel or set of channels  on the DRS4. In the process of testing this modifed version for data taken on all 4 channels, I encountered problems with decoding some of the event data. More specifically, upon hitting a certain event in some channel, the histograms for that channel would no longer be filled and the histograms for subsequent channels would not be filled with any event at all. 

After considerable bug hunting, I discovered the source of this problem was due to the break statement in the following code extract from the ROOT to binary macro:

 for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < 1)
         break;

For some events apparently, the event header fails to be read properly (fread line returns 0 in this case). Moreover, when I used the feof and ferror functions on a particular file I was testing, the feof function returned a value of 1.

So my questions deal with two scenarios.

Firstly, in the event of an fread error, is a break statement is necessary? Is it not possible to skip the voltage data for those events whose event header fails to be read properly? Or is it the case that when some "corrupted" event header is encountered, all waveform data subsequent to that event is likewise corrupted? If the former is the case, is it advisable to replace the break condition with an fseek line that advances the position indicator of the stream by an additional 2052*n_channels + 32 bytes (in accordance with the binary file specifications of page 25 on the DRS4 manual) so that the next set of voltage data can be read? 

Secondly, in the case of an end of file error, does there exist any possible solution? Or is such an error an indication of a faulty drs4 channel or corrupted binary file? 

Any help with the aforementioned issues would be greatly appreciated.

 

Abhishek

 

 

 

  562   Thu Nov 10 22:07:40 2016 Stefan RittBreak Statements in DRS4 Binary to ROOT Macro

You're right, fread() return the number of objects read, so indeed it should be one if successful.

Abhishek Rajput wrote:

Hello,

I am wondering why the code should be changed to i < sizeof(eh), since doesn't fread(&eh,sizeof(eh),1,f) return 1 in this scenario? I've confirmed with a cout statement that this is the case, so this break condition will therefore always trigger as sizeof(eh) is 32 bytes. 

Either way, I believe I figured out my problem. In my revised version of your code, I had two nested loops, the outer one being a loop over the channels and the inner one being a loop over the events. However, I really should have been doing the reverse considering the binary structure of the file.  Otherwise, the end of the file will be reached for only a single iteration of the channel loop if I choose to loop through all the events in the data file.

Once I modified the code to have the outer loop be over all the events and the inner one be over all the channels, I no longer suffered from breaks in the loops. 

Many thanks for your assistance. 

Abhishek 

Stefan Ritt wrote:

Hi,

fread() returns the number of bytes read and zero (I believe) if there is an end of file. So this break statement is a simple end-of-file test. There might be other erros such as hard disk failures, but these are extremely rare. 

If course the file should not end in the middle of an event header. If it does, it means the file is corrupted and truncated, and we should not continue to read that file, that's why there is the break. The internal file is just a series of bytes, it does not know about the event header, so there will be no "error" if we have for example a missing event header but a voltage array. To be correct, the code should actually read

for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < sizeof(eh))
         break;

Hope this helps,

Stefan

Abhishek Rajput wrote:

Hello,

I recently modified the binary to ROOT convertor written by Stefan (https://midas.psi.ch/elogs/DRS4+Forum/361) so it can decode data taken with any channel or set of channels  on the DRS4. In the process of testing this modifed version for data taken on all 4 channels, I encountered problems with decoding some of the event data. More specifically, upon hitting a certain event in some channel, the histograms for that channel would no longer be filled and the histograms for subsequent channels would not be filled with any event at all. 

After considerable bug hunting, I discovered the source of this problem was due to the break statement in the following code extract from the ROOT to binary macro:

 for (n=0 ; n<5 ; n++) {
      // read event header
      i = fread(&eh, sizeof(eh), 1, f);
      if (i < 1)
         break;

For some events apparently, the event header fails to be read properly (fread line returns 0 in this case). Moreover, when I used the feof and ferror functions on a particular file I was testing, the feof function returned a value of 1.

So my questions deal with two scenarios.

Firstly, in the event of an fread error, is a break statement is necessary? Is it not possible to skip the voltage data for those events whose event header fails to be read properly? Or is it the case that when some "corrupted" event header is encountered, all waveform data subsequent to that event is likewise corrupted? If the former is the case, is it advisable to replace the break condition with an fseek line that advances the position indicator of the stream by an additional 2052*n_channels + 32 bytes (in accordance with the binary file specifications of page 25 on the DRS4 manual) so that the next set of voltage data can be read? 

Secondly, in the case of an end of file error, does there exist any possible solution? Or is such an error an indication of a faulty drs4 channel or corrupted binary file? 

Any help with the aforementioned issues would be greatly appreciated.

 

Abhishek

 

 

 

 

  517   Wed Apr 27 20:04:12 2016 Abaz KryemadhiBest settings for time measurements

I am studing some pulses that are about 200-300 ns wide and a rise time of few ns,    which settings would be best for coincidence time measurements?

In some preliminary work I found for 700 MegaS the time measurement is better without time calibration (in -0.05 to 1V) rather than with time calibration in -0.5 to 0.5,  my pulses are about 60 mV.   Is it expected that always with time calibration time accuracy would be better or depends?   

Also I use this code snippet to find time for channel 1 and the same idea for chan. 2.

// find peak in channel 1 above threshold
      for (i=0 ; i<1022 ; i++)
         if (waveform[0][i] < threshold1 && waveform[0][i+1] >= threshold1) {
            tt1 = (threshold1-waveform[0][i])/(waveform[0][i+1]-waveform[0][i])*(time[0][i+1]-time[0][i])+time[0][i];
            break;
         }

 

Thanks!

Abaz

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