Hi,

we were trying to implement an automatic way to calibrate our DRS4 both in voltage and in time (we have the V5 Evaluation Board). We started from drs_exam.cpp and tried with the following lines:

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

b->SetInputRange(0);

b->CalibrateVolt(NULL);
b->CalibrateTiming(NULL);

While the timing calibration seems to work (we checked with drsosc executable), the voltage calibration in our test program seems not to do the same as in drsosc when pressing the button "Execute Voltage Calibration". Specifically we think that no primary calibration, secondary calibration or spike removal is applied when calling CalibrateVolt(). It seems that the methods to perform those tasks are implemented in Osci.ccp/Osci.h, but drs_exam.cpp uses objects of the class DRS (i.e. defined in DRS.cpp and DRS.h).

Is there a way to execute the voltage calibration in drs_exam.cpp in the same way performed within drsosc?

Cheers,

Alessio

Have you set the sampling frequency 

b->SetFrequency(5, true);

before the calibration?

Note there is also the "drscl" program, which is a ocmmand linke interface to the evaluation board. Start it, and do the calibration there:

then look at the code in drscl.cpp (around line 1097).

/Stefan

Hello All,

I too have been struggling with trying to get the drs4 (507) to work on my windows machine and I found it to be a problem with the libusb library. My solution is as follows and has worked on multiple PC's. I ran this solution after I first plugged in the drs4 and installed 507.

Go to http://zadig.akeo.ie/ and install the corresponding software.

After that, you will need to plug in the DRS4 to your computer. From there go to ‘Options’, and select ‘List all Devices’.

Finally, choose the DRS4 evaluation board from the list and press install driver and let it run. You should be fine after that. 

Best,

Steven

Dear Steven, many thanks for this information, this is very useful. I know of people having problems on Windows 10, maybe this will also help them.

Stefan

Thank you for this fantastic solution. I had almost reinstalled windows 7 to see if that would solve the issue!

All the best,

Alec

Hi,

I have a machine with Windows 10 and the solution provided by Steven works fine. To give more details, the driver installed in my case is WinUSB (i.e. libusb, v6.1.7600.16385).

Cheers,

Alessio

I don't know if this question is already documented elsewhere.

I am developing a DAQ code for the DRS evaluation board, v4 for a test beam experiment. I link parts of the existing DRS code as a library.

To understand the effect of various flags used in calls to the functions DRSBoard::GetTime() and DRSBoard::GetWave(), I performed several tests with the 100 MHz signal connected to the inputs of the chip (DRSBoard::EnableTcal()), and several tests with signals from scintillation counters.

My question is about the flag "adjustToClock" in the call to DRSBoard::GetWave(). From looking at the code, I expected it to cause the waveforms to be "rotated" to start from the trigger cell, in a similar way that the flag "rotated" in the call to DRSBoard::GetTime() does for the time array. However, "adjustToClock" seems to shift the waveforms wrongly. I.e., if I want both the time and the amplitude arrays "rotated"  to start from the trigger cell, I should set rotated=true for time and adjustToClock=false for the amplitude. This is also how these functions are called in e.g., Osci::ReadWaveforms().

Is this correct, and does this mean that the amplitude array is "rotated" already during the transfer from the board?

I am using DRS evaluation board serial #2733, firmware revision 30000.

Many thanks,

Strahinja

This is correct. Actually the amplitude array is rotated already inside the DRS4 chip. So the readout starts with the stop cell plus one. If you do not do anything, the waveform is already "rotated". If you want the waveform to start with physical cell #0, you have to "unrotate" it.

Stefan

Thanks.

Strahinja

Hello All,

Are there any design resources available for the WaveDREAM PCBA's?

Thanks In Advance,
John W.

No. This is a proprietary design.

Best,
Stefan

Stefan,

Oh, didn't realize that.

Thanks!
John

 Welcome to the DRS4 Discussion Forum. This forum contains information and discussions related to the DRS4 chip. Please subscribe to this forum to receive automatic email updates. If you have any technical questions, please feel free to post it here.

I have connected 3 signals to the DRS4 Evaluation Board V5 which look like this in the drsosc app:

Note that here I am sampling at 5 GS/s. Using this app everything works perfect.

Now I want to repeat this using the C++ API (which I am actually wrapping to use within Python, see here if interested https://github.com/SengerM/pydrs ) but can only make this to work at lower sampling frequencies up to 3.9 GS/s. This is how I am configuring the board followint the `drs_exam.cpp` file:

```python
board.set_sampling_frequency(Hz=SAMPLING_FREQ)
board.set_transparent_mode('on')
board.set_input_range(center=0)
board.enable_trigger(True,False) # Don't know what this line does, it was in the example `drs_exam.cpp`.
board.set_trigger_source('ch4')
board.set_trigger_level(volts=-.1)
board.set_trigger_polarity(edge='falling')
board.set_trigger_delay(seconds=TRIGGER_DELAY)

```

The full code is here https://github.com/SengerM/pydrs/blob/master/tests/test_drs.py but anyway, my previous snippet can be considered as pseudo-code and if more details needed I can provide.

This is what I get as I increase the sampling frequency:

Up to 3.95 GS/s it works perfectly. At >= 4 GS/s it just never triggers. A few times I was able to make this work at 4 and 5 GS/s playing with the trigger delay, but this seemed to be some kind of random luck because I was not able to replicate it even with the same values.

Any help is appreciated.

Best,
Matías.

Unfortunately I have not idea what the problem could be. In principle the trigger should be independent of the sampling speed, since the trigger is only made with a discriminator and a flip-flop. The hardware must be ok since you see the trigger with the oscillocope app. All you can do is to go through the sorce code of the oscilloscope app, especially drsosc/Osic.cpp::ScanBoards(), SetTriggerLevel(), SetTriggerPolariy() etc. to make sure you do the same calls as the oscilloscope app.

Stefan

I have seen in the app that the trigger source buttons do something different than the "or" and "transparent trigger" buttons:

If I enable the setup from the right, i.e. OR in CH4 and "Enable Transparent Trigger" the app stops triggering. This is the configuration that seems to be applied in the `drs_exam.cpp` code if I am not mistaken. For some reason in that code it still triggers (I have modified the code to trigger on CH4 instead of CH1 and the trigger level, polarity, etc.).

What does the button in the left actually do? The circular checkbox with the "4" I mean. This is the trigger configuration I want to get in the C++ code.

I also don't know what the function `DRSBoard::EnableTrigger` does, what is the meaning of `flag1` and `flag2`? In my code there is a call to this function which I copied from the example.

Sorry for the spam. Just want to let you know that I was able to solve the problem, it was all due to a `float` being casted as `int` in the Python binding. Now it works like a charm.

 Hi Stefan,

I'm trying to add the averaging feature to the oscilloscope instead. I have a basic knowledge in C++ so I'm having problem finding the initial place (places) of the data acquisition. furthermore, I saw you already made an averaging possibility for some of the features in the program at the measure window.
Can you please tell we in which of the programs of the Scope (and in what line if possible) can I find the initial\main data acquisition so I could follow it from there, and where is the location of the averaging function you already made?

have a nice week,

Tmiron

The averaging possibility in the measure window is just a "place holder" for future extensions, which are not yet implemented.

A good point to implement averaging is in the function Osci::ReadWaveforms() in Osci.cpp.

/Stefan