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ID Date Authordown Subject
  790   Tue May 26 11:10:27 2020 xgggDomino wave

Hi Stefan,

According to the datasheet DRS_rev09, the write signal is always 16 cells wide. So when the domino wave runs in infinite mode and be stopped by setting DENABLE low , there are always 16 cells capicitors tracking the input signal . It means that the effective sample cells is 1024-16=1008? That's confusing. 

  257   Sun May 26 13:08:52 2013 tmiron alon 

Hallo,
I'm using DRS4 Evaluation Board Rev 4.0 and I'm trying to change the output of the samples to be an average of  #  measurements (1000 or even more)
during the process I have encountered some difficulties I hope you will be able to help me  with:

1. the DRS chip have 8 channels but the Evaluation board have only 4 channels. does the default mode of the DRS in the Evaluation Board is 1024 bins for each channel or 2048?

2. in the readout mode, does it samples all the 1024 bins waveform from a channel and then move to the next one, or after each bin it move to the next channel?

3. In the file "drs4_eval4_app.vhd", I have a problem finding the names of the signals that represents the registers bits which tell me what is the number of the bin (1-1024) the ADC is reading from the DRS, and the signals

that represents registers A0-A3. can you send me their names? 

 

4. In another matter- is the -0.5V to 0.5V is the  upper and lower  limit of the input (or just a working range), and if not what is the limit for AC?  is there a fuse on the board in case of overload from the input? (I didn't see  it in the User's Manual, but I didn't know if you will mention it there in case there is one).

thanks in advance and have a nice day,

Tmiron

  259   Fri Jun 7 11:44:17 2013 tmiron alonthank you

Stefan Ritt wrote:

tmiron alon wrote:

Hallo,
I'm using DRS4 Evaluation Board Rev 4.0 and I'm trying to change the output of the samples to be an average of  #  measurements (1000 or even more)
during the process I have encountered some difficulties I hope you will be able to help me  with:

1. the DRS chip have 8 channels but the Evaluation board have only 4 channels. does the default mode of the DRS in the Evaluation Board is 1024 bins for each channel or 2048?

2. in the readout mode, does it samples all the 1024 bins waveform from a channel and then move to the next one, or after each bin it move to the next channel?

3. In the file "drs4_eval4_app.vhd", I have a problem finding the names of the signals that represents the registers bits which tell me what is the number of the bin (1-1024) the ADC is reading from the DRS, and the signals

that represents registers A0-A3. can you send me their names? 

 

4. In another matter- is the -0.5V to 0.5V is the  upper and lower  limit of the input (or just a working range), and if not what is the limit for AC?  is there a fuse on the board in case of overload from the input? (I didn't see  it in the User's Manual, but I didn't know if you will mention it there in case there is one).

thanks in advance and have a nice day,

Tmiron

1. All 8 channels are read out, but only 4 are displayed in the oscilloscope.

2. It reads all 1024 bins from a channel, then switch to the next channel.

3. The ADC readout happens in lines 1576+. The register for the sample count is drs_sample_count, and the signal for the address is drs_addr.

4. The evaluation board manual explicitly mentions the maximum allowed input range on page 5.

/Stefan 

Thank you for the answer.

Have a nice week,

Tmiron.

  260   Mon Jun 10 14:09:13 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

Hallo,
I'm using DRS4 Evaluation Board Rev 4.0 and I'm trying to change the output of the samples to be an average of  #  measurements (1000 or even more)
during the process I have encountered some difficulties I hope you will be able to help me  with:

1. the DRS chip have 8 channels but the Evaluation board have only 4 channels. does the default mode of the DRS in the Evaluation Board is 1024 bins for each channel or 2048?

2. in the readout mode, does it samples all the 1024 bins waveform from a channel and then move to the next one, or after each bin it move to the next channel?

3. In the file "drs4_eval4_app.vhd", I have a problem finding the names of the signals that represents the registers bits which tell me what is the number of the bin (1-1024) the ADC is reading from the DRS, and the signals

that represents registers A0-A3. can you send me their names? 

 

4. In another matter- is the -0.5V to 0.5V is the  upper and lower  limit of the input (or just a working range), and if not what is the limit for AC?  is there a fuse on the board in case of overload from the input? (I didn't see  it in the User's Manual, but I didn't know if you will mention it there in case there is one).

thanks in advance and have a nice day,

Tmiron

1. All 8 channels are read out, but only 4 are displayed in the oscilloscope.

2. It reads all 1024 bins from a channel, then switch to the next channel.

3. The ADC readout happens in lines 1576+. The register for the sample count is drs_sample_count, and the signal for the address is drs_addr.

4. The evaluation board manual explicitly mentions the maximum allowed input range on page 5.

/Stefan 

 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

  263   Thu Jul 4 08:32:11 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

Stefan Ritt wrote:

tmiron alon wrote:

Hallo,
I'm using DRS4 Evaluation Board Rev 4.0 and I'm trying to change the output of the samples to be an average of  #  measurements (1000 or even more)
during the process I have encountered some difficulties I hope you will be able to help me  with:

1. the DRS chip have 8 channels but the Evaluation board have only 4 channels. does the default mode of the DRS in the Evaluation Board is 1024 bins for each channel or 2048?

2. in the readout mode, does it samples all the 1024 bins waveform from a channel and then move to the next one, or after each bin it move to the next channel?

3. In the file "drs4_eval4_app.vhd", I have a problem finding the names of the signals that represents the registers bits which tell me what is the number of the bin (1-1024) the ADC is reading from the DRS, and the signals

that represents registers A0-A3. can you send me their names? 

 

4. In another matter- is the -0.5V to 0.5V is the  upper and lower  limit of the input (or just a working range), and if not what is the limit for AC?  is there a fuse on the board in case of overload from the input? (I didn't see  it in the User's Manual, but I didn't know if you will mention it there in case there is one).

thanks in advance and have a nice day,

Tmiron

1. All 8 channels are read out, but only 4 are displayed in the oscilloscope.

2. It reads all 1024 bins from a channel, then switch to the next channel.

3. The ADC readout happens in lines 1576+. The register for the sample count is drs_sample_count, and the signal for the address is drs_addr.

4. The evaluation board manual explicitly mentions the maximum allowed input range on page 5.

/Stefan 

 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 

Hi Stefan,

I have been trying to compile my changes to the program, but have a problem with the "wxWidgets". can you tell me which version of the wxWidgets and which c++ program did you use to built the drs4's scope program?

I'm using "microsoft visual c++ 2010 express", and the closest I got to compile something was with the wxWidgets 2.8.12 version (It's tell me I'm missing the file "wxmsw28d_core.lib" although I built it).

have a nice day,

Tmiron.

  265   Thu Jul 4 09:07:24 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

Stefan Ritt wrote:

tmiron alon wrote:

Stefan Ritt wrote:

tmiron alon wrote:

Hallo,
I'm using DRS4 Evaluation Board Rev 4.0 and I'm trying to change the output of the samples to be an average of  #  measurements (1000 or even more)
during the process I have encountered some difficulties I hope you will be able to help me  with:

1. the DRS chip have 8 channels but the Evaluation board have only 4 channels. does the default mode of the DRS in the Evaluation Board is 1024 bins for each channel or 2048?

2. in the readout mode, does it samples all the 1024 bins waveform from a channel and then move to the next one, or after each bin it move to the next channel?

3. In the file "drs4_eval4_app.vhd", I have a problem finding the names of the signals that represents the registers bits which tell me what is the number of the bin (1-1024) the ADC is reading from the DRS, and the signals

that represents registers A0-A3. can you send me their names? 

 

4. In another matter- is the -0.5V to 0.5V is the  upper and lower  limit of the input (or just a working range), and if not what is the limit for AC?  is there a fuse on the board in case of overload from the input? (I didn't see  it in the User's Manual, but I didn't know if you will mention it there in case there is one).

thanks in advance and have a nice day,

Tmiron

1. All 8 channels are read out, but only 4 are displayed in the oscilloscope.

2. It reads all 1024 bins from a channel, then switch to the next channel.

3. The ADC readout happens in lines 1576+. The register for the sample count is drs_sample_count, and the signal for the address is drs_addr.

4. The evaluation board manual explicitly mentions the maximum allowed input range on page 5.

/Stefan 

 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 

Hi Stefan,

I have been trying to compile my changes to the program, but have a problem with the "wxWidgets". can you tell me which version of the wxWidgets and which c++ program did you use to built the drs4's scope program?

I'm using "microsoft visual c++ 2010 express", and the closest I got to compile something was with the wxWidgets 2.8.12 version (It's tell me I'm missing the file "wxmsw28d_core.lib" although I built it).

have a nice day,

Tmiron.

I guess it should work with 2.8.12. Try to compile their examples, and consult their documentation if it does not work. I cannot give support for a package I have not written.

/Stefan 

My problem is not with wxWidgets itself but with links your program is doing to the wxWidgets. if you can please tell me the wxWidget version you used, I'll use this one instead the version I'm using and I think it will solve the problem.

Tmiron.

  267   Thu Jul 4 10:01:06 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

 

My problem is not with wxWidgets itself but with links your program is doing to the wxWidgets. if you can please tell me the wxWidget version you used, I'll use this one instead the version I'm using and I think it will solve the problem.

Tmiron.

I currently use version 2.9.4, but chances are high that it will work with 2.8.12.

/Stefan 

 but was version 2.9.4 the one you used when you built  Version 4.0.0 of the DRS4 oscilloscope program, or was it an erilar version, and if so, do you remeber what version it was?

tmiron.

  274   Tue Jul 16 10:02:28 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

Stefan Ritt wrote:

tmiron alon wrote:

 

My problem is not with wxWidgets itself but with links your program is doing to the wxWidgets. if you can please tell me the wxWidget version you used, I'll use this one instead the version I'm using and I think it will solve the problem.

Tmiron.

I currently use version 2.9.4, but chances are high that it will work with 2.8.12.

/Stefan 

 but was version 2.9.4 the one you used when you built  Version 4.0.0 of the DRS4 oscilloscope program, or was it an erilar version, and if so, do you remeber what version it was?

tmiron.

I used 2.8.12 for Version 4.0.0.

/Stefan 

 Hi Stefan.

I managed to add the averaging possibility to the oscilloscope program, but it runs too slow, so now I'm tring to add this option to the example file you attached to the program (drs_exam.cpp).
My problem is that when I run the file is not passing  the stage of getting the trigger. (it just wait after writing the line "Waiting for trigger...")
When testing the software, I work with a signal of up to 10 MHz, limited in voltage to the DRS Eval 4 ability, and I connect the signal to channel 1,from it by default is supposed to get the trigger. I also tried to change the channel settings to other channels or external trigger, and use them,  but it still not working.

I found out that the problem is related to the line "while (b->IsBusy());" in the code, but I have a problem understanding what the function "IsBusy" do and how it's work.

Can you please explain me a bit what this function does?

have a nice day,

Tmiron

  280   Sun Jul 28 09:52:25 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

tmiron alon wrote:

Hi Stefan.

I managed to add the averaging possibility to the oscilloscope program, but it runs too slow, so now I'm tring to add this option to the example file you attached to the program (drs_exam.cpp).
My problem is that when I run the file is not passing  the stage of getting the trigger. (it just wait after writing the line "Waiting for trigger...")
When testing the software, I work with a signal of up to 10 MHz, limited in voltage to the DRS Eval 4 ability, and I connect the signal to channel 1,from it by default is supposed to get the trigger. I also tried to change the channel settings to other channels or external trigger, and use them,  but it still not working.

I found out that the problem is related to the line "while (b->IsBusy());" in the code, but I have a problem understanding what the function "IsBusy" do and how it's work.

Can you please explain me a bit what this function does?

have a nice day,

Tmiron

The function b->IsBusy() returns true if there has been no trigger. So "while (b->IsBusy());" is simply an endless loop until the board triggered. Please check your signals and trigger configuration. Maybe you have to adjust the trigger level or polarity via b->SetTriggerLevel(). Try signals with lower event rates. Verify that the board triggers with the DRSOsc program, you can then read off the optimal trigger level from there. 

/Stefan

Hi satefan,

I did some debug on the DRSOsc program and saw that everywhere you used the function "IsBusy()", you used it with "SoftTrigger()", which (to my understanding) create a software trigger. did you used another function, other than "ISBusy", that check the hardware trigger?

have a nice day,

Tmiron.

  285   Mon Aug 12 15:08:17 2013 tmiron alonadd an average ability to the Scope

Stefan Ritt wrote:

Hi satefan,

I did some debug on the DRSOsc program and saw that everywhere you used the function "IsBusy()", you used it with "SoftTrigger()", which (to my understanding) create a software trigger. did you used another function, other than "ISBusy", that check the hardware trigger?

have a nice day,

Tmiron.

No. IsBusy() is the only way the hardware trigger is checked. If there is no hardware trigger, you can issue a "fake" trigger (called software trigger) to stop the acquisition. This happens for example if you switch DRSOsc to "Auto" trigger instead of "Normal" trigger, very similar than a normal oscilloscope does.

/Stefan 

 hallo stefan,

I managed to fixed the problem. The problem was with the number I inserted to the function "b->SetTriggerSource" th get external trigger (it suppose to be "16" and not "4" or "12" as I understood from the function's comments).

Right now I'm trying to speed up the number of wavefrom  per second. I'm using your  drs_exam.cpp program you wrote as my basic program. When you wrote it you used the function "b->StartDomino()" inside the loop, which means that before every trigger you gave him a command to start the domino-wave.

From  the "DRS4 datasheet" (page 8) I understand that I can bypass the need to restart the  domino-wave by using "b->SetDominoActive(1)" and "b->SetDominoMode(1)", but when I tried it didn't work (the waveform I got every readout remain the same which means the dominowave froze after the first readout).

Am I understanding wrong or do I need to add somthing more\else so the domino-wave will not stop after each readout? is there any hazard by doing that, as mentiond in page 8 of the the datasheet?

thanks again,

Tmiron.

  856   Sat Jan 15 09:13:42 2022 student_rikuI want to know about the readout

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?

  861   Wed Jan 26 06:44:11 2022 student_rikuI want to know about the readout

Dear Stefan

Thanks a lot.

I solved it.

 

Stefan Ritt wrote:
student_riku wrote:

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

Yes, as desceribed in the manual .

student_riku wrote:

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?

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

 

  154   Wed Feb 22 11:36:51 2012 sonalDRS4- analog pulse counting

Hello Sir,

Regarding to analog pulse counting by using DRS4 Rev.2.0 board, you have said that "There is a way to perform the counting dead time free, but that requires the V4 board, which has a hardware comparator on all four channels (The V2 board has only one comparator and a multiplexer). The output of these comparators go directly to the FPGA, which can then trigger on these signals. In principle one could implement a hardware counter in the FPGA, which works practically dead time free. But this requires a new firmware which has to be written. Either you do it yourself using the Xilinx development tools, or you wait until I find some time to implement this, which could take a couple of weeks or even months."

I am interested in it. I have DRS4 Rev.2.0 board. I have FPGA and Microcontroller firmware for this board. How can I implement this concept of counting pulses?

 


  576   Wed Nov 30 17:48:39 2016 samridha kunwarDRS4 Initiation

I am having a general problem getting read back using the ROI mode.  In the transparent mode everything looks good. These are the steps that I take:

1) configure register (b"11111111",addr = "1100")

2) configure write shift register (b"11111111", addr = "1101")

3)  assert DENABLE and DWRITE

4) wait for trigger

5) on trigger deassert DWRITE

6) Strobe RSRLOAD

7)Set drs4 address to enable all channels (address = "1001")

8)give n SRCLK pulses

9) goto 3 and repeat.

 

Am I missing something? Everything looks straight forward based on the manual yet in the readout mode I only get noise. I do get the stop position on SROUT and the refclk is at 475 KHz as desired and I get the desired behaviour  for DTAP toggling at the same frequency as refclk.

  578   Fri Dec 2 15:32:52 2016 samridha kunwarDRS4 Initiation

Thanks for replying Stefan.

I was more so just concerned with the steps in the firmware when I had asked. However, yes the ROFS (1.05V) and O-OFS (0.9 V was 1.3 V earlier but, changed this becasue of ADC input requirements) are per spec, the VDD voltages are all there and input voltages are within the rails and finally the RSLOAD  (16 ns) too is ok. Looking at your eval board firmware , on appearance it looks exactly like what I am doing. I thought maybe I was/ still am missing some intermediate addressing stage. What I wrote earlier is what I still have.

Stefan Ritt wrote:

Uhh, there are 1000 things which might be wrong. A bit like "my car is not working, it makes strange noise". Without having a look under the hood, there is just some wild guessing:

- Is your ROFS input at the right value? Your O-OFS?

- All VDD voltages there? Input voltage outside the rails?

- Your RSLOAD pulse long enough (>10ns)

- What happens if you put a really big sinal at the input, like 100 MHz sine wave with 2V p-p

The easiest is to have a look at the evaluation board and copy your new board like 1:1, also copy the VHDL readout code. Much easier that to start from scratch.

Stefan

 

 

samridha kunwar wrote:

I am having a general problem getting read back using the ROI mode.  In the transparent mode everything looks good. These are the steps that I take:

1) configure register (b"11111111",addr = "1100")

2) configure write shift register (b"11111111", addr = "1101")

3)  assert DENABLE and DWRITE

4) wait for trigger

5) on trigger deassert DWRITE

6) Strobe RSRLOAD

7)Set drs4 address to enable all channels (address = "1001")

8)give n SRCLK pulses

9) goto 3 and repeat.

 

Am I missing something? Everything looks straight forward based on the manual yet in the readout mode I only get noise. I do get the stop position on SROUT and the refclk is at 475 KHz as desired and I get the desired behaviour  for DTAP toggling at the same frequency as refclk.

 

 

  33   Wed Feb 10 02:57:55 2010 pepe sanchez lopezHello

hello i am an student and i want to do my final project with drs4 board and i really can´t find how to open waveform file and how can i save or opened many of them quickly.

if you can tell me how i will be very grateful.

thanks,

kind regards.

  457   Wed Dec 23 15:38:14 2015 mony orbachDtap stops toggling after 40msec

Hi

the drs4 start to generate Dtap signal after reset and standard configuration.

while in reset Denable and  Dwrite are low

after reset we put Denable in high

the Dtap starts to toggle, and the plllck stabilizes on about 1V.  

After 40Msec the Dtap stops to toggle and the plllck go to 2.5V

Why do the Domino stop working?

 

Thanks, Mony

  459   Thu Dec 24 10:51:31 2015 mony orbachDtap stops toggling after 40msec

my refclk is 1.25Mhz

what are the inputs and voltage you need to see?

Avdd and Dvdd are 2.5v

Denable is "1" Dwrite "0"

currently i am doing an external reset cycle, after that i am doing the configuration cycle.

should i relay on the internal reset?

the Dtap is toggling for 33.8msec and then just stops.

 

Thanks, Mony 

Stefan Ritt wrote:

No idea what you do wrong. I need to see oscilloscope traces for all your inputs and voltages. What is your REFCLK input?

mony orbach wrote:

Hi

the drs4 start to generate Dtap signal after reset and standard configuration.

while in reset Denable and  Dwrite are low

after reset we put Denable in high

the Dtap starts to toggle, and the plllck stabilizes on about 1V.  

After 40Msec the Dtap stops to toggle and the plllck go to 2.5V

Why do the Domino stop working?

 

Thanks, Mony

 

 

  Draft   Sun Dec 27 15:06:59 2015 mony orbachDtap stops toggling after 40msec

Hi

We have some meesurs to show (attached)

  1. Dtap and Denable
  2. Dtap+Denable in zoom
  3. Dtap + Ref+
  4. Dtap + Dspeed

From the screen shots it can be seen that ref+ is not synchronized with Dtap (PLL not working correctly)

And Dspeed is going done to zero after some time.

In our system Dspeed is shorted to pllout.

So it looks like pllout do not pump the RC filter capacitors.

We tested various value of R and C's.

Also we checked that pllout is sorted to Dspeed.

 

Thanks, mony

 

 

 

Stefan Ritt wrote:

I want to see the trace on the scope for the DTAP, the REFCLK, the DENABLE and the DWRITE.

Probably (but it's just a guess), you have a problem with the soldering of the DRS chip, maybe to the PLL loop filter. Or you chose the wrong capacitor/resistor combination for the loop filter. There are ~10 other groupsl who did the same and it works for all of them, so there must be a problem on your side.

 

Stefan

 

mony orbach wrote:

my refclk is 1.25Mhz

what are the inputs and voltage you need to see?

Avdd and Dvdd are 2.5v

Denable is "1" Dwrite "0"

currently i am doing an external reset cycle, after that i am doing the configuration cycle.

should i relay on the internal reset?

the Dtap is toggling for 33.8msec and then just stops.

 

Thanks, Mony 

Stefan Ritt wrote:

No idea what you do wrong. I need to see oscilloscope traces for all your inputs and voltages. What is your REFCLK input?

mony orbach wrote:

Hi

the drs4 start to generate Dtap signal after reset and standard configuration.

while in reset Denable and  Dwrite are low

after reset we put Denable in high

the Dtap starts to toggle, and the plllck stabilizes on about 1V.  

After 40Msec the Dtap stops to toggle and the plllck go to 2.5V

Why do the Domino stop working?

 

Thanks, Mony

 

 

 

 

  462   Sun Dec 27 15:41:32 2015 mony orbachDtap stops toggling after 40msec

Hi

We have some measures to show (attached)

  1. Dtap and Denable
  2. Dtap+Denable in zoom
  3. Dtap + Refck+
  4. Dtap + Dspeed

From the screen shots it can be seen that refck+ is not synchronized with Dtap (PLL not working correctly)

And Dspeed is going done to zero after some time.

In our system Dspeed is shorted to pllout.

So it looks like pllout do not pump the RC filter capacitors.

We tested various value of R and C's.

Also we checked that pllout is sorted to Dspeed.

 

Thanks, mony

 

 

 

Stefan Ritt wrote:

I want to see the trace on the scope for the DTAP, the REFCLK, the DENABLE and the DWRITE.

Probably (but it's just a guess), you have a problem with the soldering of the DRS chip, maybe to the PLL loop filter. Or you chose the wrong capacitor/resistor combination for the loop filter. There are ~10 other groupsl who did the same and it works for all of them, so there must be a problem on your side.

 

Stefan

 

mony orbach wrote:

my refclk is 1.25Mhz

what are the inputs and voltage you need to see?

Avdd and Dvdd are 2.5v

Denable is "1" Dwrite "0"

currently i am doing an external reset cycle, after that i am doing the configuration cycle.

should i relay on the internal reset?

the Dtap is toggling for 33.8msec and then just stops.

 

Thanks, Mony 

Stefan Ritt wrote:

No idea what you do wrong. I need to see oscilloscope traces for all your inputs and voltages. What is your REFCLK input?

mony orbach wrote:

Hi

the drs4 start to generate Dtap signal after reset and standard configuration.

while in reset Denable and  Dwrite are low

after reset we put Denable in high

the Dtap starts to toggle, and the plllck stabilizes on about 1V.  

After 40Msec the Dtap stops to toggle and the plllck go to 2.5V

Why do the Domino stop working?

 

Thanks, Mony

 

 

 

 

Attachment 1: Dtap-Denable.gif
Dtap-Denable.gif
Attachment 2: dtap-Danable2.gif
dtap-Danable2.gif
Attachment 3: Dtap-refck.gif
Dtap-refck.gif
Attachment 4: Dtap-Dspeed.gif
Dtap-Dspeed.gif
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