The scalers are read out 10x per seconds, so they have an accuracy of 10 Hz. I tried a 50 Hz pulser, and measured 40 Hz, I tried 52 Hz and measured 50 Hz. This is about what you can expect.

The scaler rate is measured after the discriminator of the trigger, so the trigger level also affects the scaler reading. If you have a 100 mV pulse and your threshold is 200 mV, your scaler rate drops to zero. That can be seen best with the DRSOsc and sliding the trigger value. If you have a 50 Hz pulse with narrow (< us) pulses, things are fine. But if you use a 50 Hz square wave, then you get distorted signals due to the AC coupling which can also be confusing. See for example here: https://www.daqarta.com/dw_gg0o.htm

The 'drscl' tool is more for experts, normal users are advised to use the DRSOsc oscilloscope.

The board has to be calibrated for a given sampling speed before calibrated data can be read out. Do that with the "calib" command, specifying 5 for the sampling rate, 0 for the range (which is the middle between -0.5 and +0.5) and 1 for 1024 mode. If you then do "start", "stop", "read 0 1" you get calibrated data in mV.

Stefan

I am using the `drscl` app. My prior experience is practically zero, sorry if this is a very naive question. When I read using `read 0 1` (channel 0, with calibration) I get this:

```
Calibration not valid for board #2946
  10    3    7    4   10    8   14    5    5    9    3    4    9    8    9    4
   3    3   12    5    5   13    3    8    1    5    0    4    8    6    6    3
...etc...
```

Why does it says that the calibration is not valid? How am I supposed to go from integers to volts?

If I run the `info` command I get this:

```
==============================
Mezz. Board index:    0
DRS type:             DRS4
Board type:           9
Serial number:        2946
Firmware revision:    30000
Temperature:          43.4 C
Input range:          -0.5V...0.5V
Calibrated range:     -0.5V...0.5V
Calibrated frequency: 0.000 GHz
Status reg.:          0000009A
Control reg.:         00000000
  DMODE circular
Trigger bus:          00000000
Frequency:            1.007 GHz
```

Hi. I'm trying to evaluate livetime of the evaluation board with the hardware scaler. I'm facing a strange issue.

I took the rate with the function, DRS->GetScaler(int channel).
I guess that channels 0--3 mean the rate for the channel, and channel 4 means the counter of the trigger.
I took the 1,000 pulses generated by a pulse generator with 50 Hz.
The scaler values are ~ 39.83, not 50.
The timestamp difference between the initial event and the final event is 19.98 seconds.
1000/19.98 ~ 50, thus, the evaluation board took the pulses with enough livetime.

Can we believe the scaler value for the livetime evaluation?

Hi everyone,

Did anyone have a "missing sliders problem" in GUI (see attachment)  accompanied by the following message in the terminal.

(drsosc:4611): Gtk-WARNING **: 14:05:11.249: Negative content width -4 (allocation 20, extents 12x12) while allocating gadget (node scale, owner GtkScale)

(drsosc:4611): Gtk-WARNING **: 14:05:11.249: Negative content width -2 (allocation 0, extents 1x1) while allocating gadget (node trough, owner GtkScale)

If yes, how did you solve it?

All ideas are appreciated!

Cheers,

Dmitry

The trigger comparator is a ADCMP601 unit which requires a minimum pulse width of 3-4 ns. I see that your pulses are only 1-2 ns wide. You have to make your pulses wider in order to trigger on them.

Stefan

drs4b is now officially on these distributions:

https://repology.org/project/drs4eb/versions

enjoy

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.

Dear Stefan

Thanks a lot.

I solved it.

Yes, you've got it exactly right. Thank you, that helps a lot! 

Thomas

drsosc is a graphical application contiously acquiring data from the board, and drscl is a command line tool for debugging, as written in the manual.

The drsosc application runs indefinitely, but I guess you refer to saving data (by hitting the "Save" button in the drsosc application). Yes the save functionality has a number of events, since you cannot store data indefinitely, since your harddisk does not have indefinite space!

I kind of sense that you want to convert the "number of event to save" into "number of seconds or hours to save". This is not build into the drsosc application. It's all open source, so feel free to change the code. Alternatively, you can use the drs_exam.cpp program coming with the distribution, wich is a simpel C++ program reading the board. It has a for loop over 10 events, but you can change the code easily to run for a predetermined amount of time.

Stefan

Hello,

I'm working on a project wherein we're looking at photomultipliers. We've already acquired a DRS4 evaluation board with the intent of using it to gather our data.

I've looked at the source code for the software with the intent of maybe writing a patch to add additional functionality. I was hoping you could answer some quick questions in that regard.

Am I correct in assuming that drsosc and drscl are functionally equivalent regarding collecting data? We want to run the DRS4-EB for a predefined amount of time. However, the DRS4 scope application seems only to run for a predefined set of measurements. Have I got that right? Is there some reason to avoid running the DRS4-EB for a predefined amount of time that I should be aware of?

Appreciate any help you can provide. Thanks!

Kind regards,

Thomas

Yes, as desceribed in the manual .

I don't understand what you mean by "second week". 

Normally, you run the chip continously (DMODE=1) until you receive a trigger. Then, you typically read out the chip from the stop position by using a RSRLOAD pulse (as described unter "REGION-OF-INTEREST READOUT MODE".

Stefan

Hello, everyone.
I'm a student in Japan.
Please forgive me if this is a very rudimentary question.

Am I right in thinking that inputting 1 to DMODE (Bit0) in the configuration register will connect the 1024th cell to the 1st cell?

Also, let's assume that after sampling 1024 cells on channel 0, 200 cells are sampled in the second week.
Does the readout of 1024 cells start from cell 0?
Or does it start from the 200th cell?

1. fDOMINO is defined as fREFCLK * 2048

2. Good values can be derived from the evaluation board schematics: C1=4.7nF, C2=1nF, R=130 Ohm

3. A "1" means a logical high level. See Wikipedia: https://en.wikipedia.org/wiki/Logic_level

I also design the circuit myself. Our problem is the same. Can we communicate？

Dear Sir or Madam,

      Good morning，I am using drs4 chip, and the measured fDTAP == 1/350ns, that is, fDOMINO == 1 / 350ns * 2048 == 5.8GHz.

     I have three questions:

                              1. Is fDOMINO determined by the chip itself?

                              2. C1, C2 and R2 are TBD. I don't know how many to choose. Is there an algorithm?

                              3."Configure Write Shift Register to contain all 1's"，What, pray, is the meaning of “1's"?

                                                                                                                                                          Truely yours.

A V3 boards is already 10 years old and out of warranty. The software has no configuration to turn channels off except the channel buttons on the main page on top of the sliders. I presume the channels are broked due to some overvoltage applied to them (the V5 board is better protected against over voltage). You can send it the board for repair, but it will cost almost the same amount of money than buying a new boards.

Regards,
Stefan

Hi everyone,

I'm still looking through the forum for an answer to this question, but thought I'd go ahead and post anyway just in case it hasn't been answered yet. If it has I can take this post down.

I have a V3 board, and as far as I can tell only channel 2 gives an output. If I enable other channels using the DRS Oscilloscope software, they do show static but will not show a signal if I connect one to them (e.g. a series of subsequent square waves). A technician and I took the board out and tested all the components leading up to the microcontrollers for each channel, and everything seemed to be working fine. I thought maybe it was configured to only have one channel read an output, but I looked through the Config panel in the software and nothing seemed to indicate that.

I am a novice, and maybe I'm missing something that I didn't see in the manual. I can post screenshots if needed!

Thank you for your help!

Thanks for your advice. The problem has been solved by setting the srin again while reading out from srout.