The Cypress has its own firmware, contained in the distribution under firmware/CY7C68013A/drs_eval.c. There you can see how the data is fetched. I kind of forgot how exactly it worked, since I wrote that code back in 2011. But most if the Cypress code is just the configuration of the USB, the communication with the FPGA is kind of straight forward in the Cypress implementation. But you have to read the manual of that chip to understand it.

Unfrtunately there is no full testbench for the firmware, since I didn't have a VHDL Model of the Cypress, so I implemente dit the "hard" way ;-)

Best,
Stefan

1. Transparent mode is not needed for the hardware trigger, no idea why the code is there. You can probably remove it.

2. EnableTCal is only for the sake of having some waveforms at the input. Indeed you have to disable it to sample real signals.

3. EnableTrigger() is there to enable the hardware trigger. The flag2 is ther for historical reasons (used in older versions of the board).

4. You figured that out already yourself.

5. The functions CalibrateVolt() and CalibrateTiming() are the ones which get called if you click on volt and time calibration in the DRSOsc application. The calibration is store on the evaluation board, so you do not have to call them in your program.

You have to link against the DRS.cpp library, plus usblib, plus ... Note there is both a Makefile and a CMakeLists.txt for it. Google how to use "make" or "cmake".

Stefan

This is correct. Setting A0-A3 to 0b1101 multiplexes the Shift Write Register to SROUT, so you will either a "0" or a "1" depending on which of the two channels was written last.

Your segmented capture does unfortunately not work. Due to a bug in the silicon, the first (e.g. even) written channel gets half overwritten when you start sampling the second (odd) channel. I should remove that from the documentation.

Furthermore, reading the chip while writing on the "other side" introduces quite some additional noise. The recommended way to do simultaneous reading and writing is therefore to use two separate DRS4 chips and split the input signals to both chips, then read from one chip while writing to the other chip. This keeps the crosstalk at a minimum and both chips run at full performance.

Stefan

The full readout mode is not really recommended since you have to pull out the stop position separately. Just do the ROI readout using the RSRLOAD signal, and then do 1024 samples, which also gives you the full waveform, but also the stop position in a single readout cyclce. The "full readout mode" is more there for "historical reasons", but nobody really uses it any more.

If you are interested in all details of the control signals, I propose you have a look at the VHDL code which comes with the software distribution. It's contained in the "firmware" subdirectoy and called drs4_eval5_app.vhd

Stefan

Yes this is correct. Anyhow, even if it would be working, you would not be happy with it. After having designed ~10 boards with the DRS4 chip, I learned the hard way that any digital activity on the board during the sampling phase is strictly forbidden. You see crosstalk up to 100's of mV in some cases (with a preamplifier on the board, 10-20mV without preamp). So rule #1 is to keep the board as "quite" as possible when sampling the input. If you would readout the odd channels of the DRS4 during sampling of the even channels, you would probably get so much crosstalk that the samples are almost unusable. Even if you would do this with two DRS4 chips next to each other, you have to make sure to put proper grounding between the two chips, and operate them completely independent (like each one has it's onw contol lines going to the FPGA). Designing such boards is not so easy and takes lots of experience from the layouter.

Stefan

 Thank you for your response.

The DRS4 Rev.2.0 with one Multiplexer and a Comparator I think may be is ok for me. Since I wanted to implement counter in FPGA, I have gone through firmware but its very difficult for me to get the flow of data from DRS to USB. Could you help me to get familiar with or to get flow of the data from DRS to the USB?

Thank You,

Sonal

Hello everyone, 

The new read_binary.cpp code 

I will be very glad if anyone can help with the old version of read_binary.cpp code. The latest version I saw online was updated on June 30th, 2014, but I need the old version of the code to compare what changes were made in the latest version. This will help me to modify it and be able to read my data successfully. Thanks

Hi,

I'm currently working on a little DAQ system with four DRS evaluation boards. Do i need to apply any specific settings when using the clock in/out connectors for synchronization? I do not see anything like that in the drs_exam_multi example.

Any help would be greatly appreciated!

Best,

Simon

Thank you so much for the fast reply! I'll give it a try.

Best regards,

Simon

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

We are using the drs_exam.cpp to read out waveforms, but it seems to be outputting only sin waves on all channels - as if it was reading out the simulated waveform from the oscilloscope program if we run it without the board plugged in. Does anyone know what is causing this?

We are taking data with a pulser plugged into channel 1, which produces a single pulse with width of 8ns, and nothing plugged into channel 2. 

Our board is as follows:

Found DRS4 evaluation board, serial #2567, firmware revision 21305
Board type: 9

The output is something like the following:

Event #0 ----------------------
  t1[ns]  u1[mV]  t2[ns] u2[mV]
  0.000  -452.7   0.026  -469.3
  0.289  -460.8   0.293  -469.8
  0.413  -477.3   0.400  -481.5
  0.642  -485.3   0.650  -482.4
  0.806  -486.9   0.821  -477.8
  1.086  -476.8   1.085  -457.2
  1.183  -467.3   1.162  -446.4
  1.450  -435.6   1.459  -405.1
  1.619  -410.1   1.630  -373.3
  1.843  -366.2   1.851  -323.9
  1.945  -342.9   1.948  -298.9
  2.221  -275.7   2.210  -229.3
  2.359  -237.6   2.357  -187.6
  2.602  -165.6   2.609  -111.2
  2.687  -141.1   2.697   -84.3
  2.976   -50.5   2.987     5.5
  3.164     8.4   3.144    53.3
  3.377    73.9   3.384   124.2
  3.503   111.4   3.506   158.0
  3.753   182.0   3.769   226.9
  3.924   227.5   3.929   265.8
 

I see. Where is the code that we can use to turn off the generator? I thought the example is taking data with CH1 as the trigger.

For our board, which is BoardType == 9, it is running these lines:

      b->EnableTrigger(1, 0);           // enable hardware trigger
      b->SetTriggerSource(1<<0);        // set CH1 as source

Is that not using the hardware trigger with CH1 as the source?

Hi Rodrigo, I'm wondering how you solved your original triggering problem. We are also having trouble with collecting data continously using the example. Thanks.

Dear Stefan,

I have questions about the timing diagram of SROUT/SRIN signal to write/read a write shift register.
1) Value of SRIN signal is saved at the falling edge of SRCLK, correct? (It is written in datasheet, page12, "Bits are latched into the shift register on the falling edge of SRCLK")
2) When are 8-bits of write shift register shown through SROUT? At ridging edges of SRCLK? and with additional delay(~10ns)? or falling edges?
3) In my understanding, when SRCLK is sent to DRS4, we can read and write the values in parallel, right? If so, is it possible just to read the registers without updating the registers?

[Background]
We have two modes to set the write shift register, the first one is to always reconnect to the first line and another one is to reconnect to the same line as when DWRITE goes to Low.
We can read/write the write shift register with the first mode (channel reset, page1). But we rarely face the problem of write shift register, unexpected values are written, with the second mode. With this mode, SROUT signal is sent back to DRS from FPGA as SRIN to write the same value on the write shift register. So there is a small delay(~10ns) due to the routing (DRS->FPGA->DRS, page2). It seems SRIN signal is not stable around the falling edges of SRCLK, thus it could cause that unexpected values are written in write shifter register.
To understand the situation clearly, I'd like to know the answer to the above questions.

Thank you.

Best regards,
Seiya

Dear Stefan,

Thank you for your reply.
SRIN is directly connected to SROUT via FPGA for now, but it is unstable for the timing between clock and SRIN depending on the firmware logic.
We want to make our system more robust, so we are thinking to use a clock with a lower frequency (let's say 16.6 MHz) or change the duty cycle of a clock to keep more time between the rising edge and falling edge of a clock. This change is just for reading/writing the write shift register, we will use a 33 MHz clock for the analog readout in any case.
If we change like above, are there any concerns from the DRS4 side?

Best,
Seiya

Dear Stefan,

OK, it's good to hear! Thank you!

Best,
Seiya

Hello i cant install any the last versions that i downloaded from the dropbox, i can untar the file called drs-5.0.6 and when i type "make" while inside the extracted folder that starts working properly till a point and i get an error, its worth mention that i installed wxWidgets and could make a simple hello world that worked properly in wxWidgets.

The error that i get is the next one:

inlined from ‘bool ResponseCalibration::ReadCalibrationV4(unsigned int)’ at src/DRS.cpp:7224:35:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:95:34: warning: ‘char* __builtin___strncpy_chk(char*, const char*, long unsigned int, long unsigned int)’ specified bound depends on the length of the source argument [-Wstringop-truncation]
   95 |   return __builtin___strncpy_chk (__dest, __src, __len,
      |          ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
   96 |                                   __glibc_objsize (__dest));
      |                                   ~~~~~~~~~~~~~~~~~~~~~~~~~
src/DRS.cpp: In member function ‘bool ResponseCalibration::ReadCalibrationV4(unsigned int)’:
src/DRS.cpp:4767:11: note: length computed here
 4767 |    strncpy(calibrationDirectoryPath, fCalibDirectory, strlen(fCalibDirectory));
      |    ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/string.h:535,
                 from /usr/local/include/wx-3.3/wx/string.h:30,
                 from /usr/local/include/wx-3.3/wx/memory.h:15,
                 from /usr/local/include/wx-3.3/wx/object.h:19,
                 from /usr/local/include/wx-3.3/wx/wx.h:15,
                 from src/DRS.cpp:15:
In function ‘char* strncpy(char*, const char*, size_t)’,
    inlined from ‘void DRSBoard::GetCalibrationDirectory(char*)’ at src/DRS.cpp:4767:11,
    inlined from ‘bool ResponseCalibration::ReadCalibrationV3(unsigned int)’ at src/DRS.cpp:7066:35:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:95:34: warning: ‘char* __builtin___strncpy_chk(char*, const char*, long unsigned int, long unsigned int)’ specified bound depends on the length of the source argument [-Wstringop-truncation]
   95 |   return __builtin___strncpy_chk (__dest, __src, __len,
      |          ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
   96 |                                   __glibc_objsize (__dest));
      |                                   ~~~~~~~~~~~~~~~~~~~~~~~~~
src/DRS.cpp: In member function ‘bool ResponseCalibration::ReadCalibrationV3(unsigned int)’:
src/DRS.cpp:4767:11: note: length computed here
 4767 |    strncpy(calibrationDirectoryPath, fCalibDirectory, strlen(fCalibDirectory));
      |    ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
g++ -g -O2 -Wall -Wuninitialized -fno-strict-aliasing -Iinclude -I/usr/local/include -DOS_LINUX -DHAVE_USB -DHAVE_LIBUSB10 -DUSE_DRS_MUTEX -I/usr/local/lib/wx/include/gtk3-unicode-3.3 -I/usr/local/include/wx-3.3 -D_FILE_OFFSET_BITS=64 -DWXUSINGDLL -D__WXGTK__ -pthread -c src/averager.cpp
g++ -g -O2 -Wall -Wuninitialized -fno-strict-aliasing -Iinclude -I/usr/local/include -DOS_LINUX -DHAVE_USB -DHAVE_LIBUSB10 -DUSE_DRS_MUTEX -I/usr/local/lib/wx/include/gtk3-unicode-3.3 -I/usr/local/include/wx-3.3 -D_FILE_OFFSET_BITS=64 -DWXUSINGDLL -D__WXGTK__ -pthread -c src/ConfigDialog.cpp
In file included from include/DRSOscInc.h:25,
                 from src/ConfigDialog.cpp:7:
include/DOFrame.h: In member function ‘bool DOFrame::GetRefclk()’:
include/DOFrame.h:111:46: error: ordered comparison of pointer with integer zero (‘bool*’ and ‘int’)
  111 |    bool GetRefclk()        { return m_refClk > 0; }
      |                                     ~~~~~~~~~^~~
make: *** [Makefile:81: ConfigDialog.o] Error 1
 

Dear All,

I'm troubleshooting a board which uses the DRS4 and adopts an analog front end very similar to the evaluation board. As a result, we rely on the eval board as a reference. In doing so we've encountered an issue in the manual:

The high resolution photo in Figure 1. is useful, but it seems to correspond to an older version of the board. For instance, the RF switch can't correspond to the schematics of Rev5.1 in the appendix.

Request: Could the manual be updated with a high resolution image of Rev5.1. Also, could a high resolution of the bottom side of the board be included in the manual? This is desirable since it has the version number and contact information, so it will remove any ambiguity about what board you're looking at and what schematics you should refer to.

A second question, which might be overly broad: what is the impact of installing the optional components (marked * in the schematics) on the analog front end? Why are a lot of these left uninstalled on the eval board?

Thanks,

Sean