Sorry the late reply.

In V4, triggering has changed. You can trigger now on an OR or AND of channels. Therefore you have to supply a bitmask, where the 1st bit = CH1, 2nd bit = CH2 and so on. Have a look at the most recent drs_exam. It contains code:

   /* use following lines to enable hardware trigger on CH1 at 50 mV positive edge */
   if (b->GetBoardType() == 8) {     // Evaluaiton Board V4 
      b->EnableTrigger(1, 0);           // enable hardware trigger
      b->SetTriggerSource(1<<0);        // set CH1 as source
   } else {                          // Evaluation Board V3
      b->EnableTrigger(0, 1);           // lemo off, analog trigger on
      b->SetTriggerSource(0);           // use CH1 as source
   } 

So if you want CH1 && CH2, you look at the source code of SetTriggerSource. It contains

      // Set trigger configuration
   // OR  0=CH1, 1=CH2, 2=CH3, 3=CH4, 4=EXT
   // AND 8=CH1, 9=CH2, 10=CH3, 11=CH4, 12=EXT

So an AND between CH1 and CH2 needs a

    b->SetTriggerSource(1<<8 | 1<<9);

Your code looks interesting. Do you have a screenshot or can you explain what it does? 

    That's it? Thank you for your comprehensive answer.

 Sure, you can set the trigger level with the vertical slider (see attached figure). The trigger level works form -0.5V to +0.5V. Just like with a normal oscilloscope. I thought this would be obvious...

Can I adjust the internal trigger DRS oscilloscope for signal extraction 0.5 volts (for example) from any of the four channels. In our case, there is a lot of noise with low amplitude, which must be removed during the registration. We need to record the individual pulses of higher amplitude than the noise. So we want to use the internal trigger DRS oscilloscope to cut this noise by setting up its threshold amplitude noise.

Sorry, I don't understand that question. The DRS4 Evaluation board input signal range is 1V. If you have larger signals, you have to attenuante them externally.

/Stefan 

How to configure DRS oscilloscope for the oscillations with an amplitude greater than the value of the exposed
in the trigger (internal). 

 I switched from rev 3 to rev 4 board, but have some problems with triggering, board is now waiting for trigger (rev.3 is working). How to do in drs_exam.cpp for example triggering on Ch0 && CH1 ?

Software 4.0.0, windows version.

Here is old trigger initialisation: 

b->EnableTrigger(0,1);

b->SetTriggerSource(0);

b->SetTriggerLevel(0.25, false);

b->SetTriggerDelayNs(0);

Btw. Is it possible to set up different trigger Levels for each channel ?

(If there is some interest here is my code in Qt, still aplha) http://sourceforge.net/p/qtpals/code

After power-up reset, these registers are all set to "1", which should be ok to start.

BTW, Jinhong Wang <wangjinh@mail.ustc.edu.cn> from your institute hast the chip correctly working. Maybe he can help you in a more direct way than I can.

 "Keep Denable and Dwrite low (required during power-on, see elog:10), set Dspeed to 2.5V, then rise Denable and Dwrite. You should see Dtap toggling at about 2.4 MHz. "

In this process ,  should i config any registers( WSR,WCR,CR  ) ?

The first thing to make work is to have DTAP oscillating with fsamp/2048. Keep Denable and Dwrite low (required during power-on, see elog:10), set Dspeed to 2.5V, then rise Denable and Dwrite. You should see Dtap toggling at about 2.4 MHz. If not, double check all supply voltages, and especially all soldering points. The QFN package is a bit hard to solder.

/Stefan 

When Denable and Dwrite is high , the voltage of PLLOUT is 0 V.  And  the Dtap is turn high with no delay when the Denable turns high.

After power up and configuration(the WSR,WCR,CR are all set to 11111111), the readout data is no change whenever the input analog signal and rofs,bias,oofs changes. I have test useing the DAC to supply the Dspeed voltage, and change a new DRS4 chip, but all is the same. The readout data is strange : the first about 100 cells is rise or fall  and the last 900 cells is out of the range of ADC.

So how should I do for debugging the drs4 now.

That`s very bad news for me. I don`t have much time to study & write C programming...

Anyway, Thank you very much Stefan.

Best regards.

Gyuhee.

You have to write your own program. DRS Oscilloscope does not (yet) support this. Take drs_exam.cpp as a starting point and try to extend it to two boards. One tricky point is that the external trigger may only fire AFTER the two boards have been read out. So you need some means of re-enabling the external trigger after you read out both boards.

Stefan 

 Hi.

I asked about using multi boards some days ago, and I got answer to use external trigger. (Thanks Stefan!)

And here is another question. I made two external triggers and try to acquire coincidence data using two boards. but DRS Oscilloscope program can connect only one board and don`t acquire both of them simultaneously.

So I tried to use two computer for each board separately, but, well, you already know, I failed to acquire because two computers don`t promise to synchronize the two boards acquisition.

Is there any method to solve this problem?

1. I want to acquire coincidence data from the two DRS 4 Evaluation board V4 simultaneosly.

2. I have external trigger to provide the two boards at the same time.

3. How can I get data from the two boards?

Best regards.

Gyuhee.

I made a pre-compiled package for Mac OSX 10.8 (Mountain Lion), so one should be able to install the DRS Oscilloscope software with one mouse click on a recent Mac.

The Makefile in the tar ball now also supports OSX 10.8, so one could even compile it from the sources on a Mac, after libusb-1.0 and wxWidgets have been installed. That might then also work on older versions of OSX.

In addition, the software has been adaptes so that it compiles nicely on a Raspberry Pi (http://www.raspberrypi.org), a screenshot has been attached. Together with a Raspberry Pi and an old screen, the evaluation board is one of the cheapest available oscilloscopes.

 Thanks Stefan.

I will build external trigger system. 

This mode is not yet implemented in firmware. Maybe I find some time towards the end of this year to add this. At the moment, you have to build and external trigger to synchronize the two boards. There are also 16-channel boards on the market where you would not need a multi-board mode. Just Google for "DT5742".

/Stefan

 Hi.

I have 2 DRS4 evaluation V4 boards, and I want to use these 2 board to multi board DAQ system for 4 ch vs 4 ch DAQ.

But there is no option for multi board use. I just only find the multi board trigger mode check button on DRS4 Oscilloscope program, but I couldn`t check. 

Is there any method to use multi board?

Best regards.

Gyuhee.

 Yes, yes, no. To get spike removals, you need the function RemoveSpikes from Osci.cpp in the DRSOsc project.