Re: [casper] High clock freq timing error

2011-04-25 Thread mandana
Hi all,

I am trying to compile a slightly modified version of tut4 for
850MHz ADC sampling rate. I am using bwrc branch of the
casper_library as it was suggested that it has latest fixes for fft and
pfb_fir blocks. I have deleted those blocks and re-dropped them from the
latest bwrc lib.

I followed suggestions listed on the following thread:
http://www.mail-archive.com/casper@lists.berkeley.edu/msg01804.html

(Some of the suggestions do not really apply anymore)
I was able to compile for 820MHz, but I still get timing errors on pfb_fir
block when compiling for 860MHz.

Has anyone been able to compile tut4 for higher clock rates? Any suggestions?

Thanks,
Mandana

 On 01/03/2011 2:44 PM, Danny Price wrote:   Hey
Daniel

   Things start to get sticky when you go above 200MHz FPGA clock
 with that tute 3 spectrometer, so you might have to tweak some
  things under the hood to get it working at 250MHz. Have a look at
  this thread:
   http://www.mail-archive.com/casper@lists.berkeley.edu/msg01804.html

   As Mark said, have a look at the detailed timing report to try and
 track down the rogue blocks.

   Also, make sure you're using an up-to-date git repository; Andrew
made some useful changes to the pfb and adc blocks to make them
  behave nicer at higher frequencies (thanks Andrew!). In
particular, these commits are a must:
   
http://casper.berkeley.edu/git/?p=mlib_devel/bwrc.git;a=commit;h=d81d7523efbbb7668ea04a4b3ce3ddc3107ad875
http://casper.berkeley.edu/git/?p=mlib_devel/bwrc.git;a=commit;h=37c90e2b98da3a48a4d3f7b67980fdd28b32a6ce

   To summarize all this, to get the spectrometer working at 250MHz I
 would suggest:
   * updating to the latest git repository
   * deleting the PFB_FIR_REAL block and dragging in a new one from
   your newly updated library
   * deleting the FFT block too, and adding in a new one
   * changing to the settings mentioned here:
http://www.mail-archive.com/casper@lists.berkeley.edu/msg01804.html

   Hope that makes sense!

   Cheers and good luck
   Danny


   On 01/03/2011 22:17, Mark Wagner wrote:   Hi Daniel,
  From the Matlab command prompt, you can type
dos('timingan') and then open the timing report
 ./XPS_ROACH_base/implementation/system.twx from the
analyzer.You'll see where the timing issues
are occurring (i.e.   negative slack).  You can
then go back to your design and add   registers
or delays where appropriate to hopefully allow data
 to propagate in a reasonable time.  This takes up
resources   though, and can sometimes make
things worse.  If you're unable   to get the
design to meet timing at this point, it may behoove
 you to use the floor planner.
  Mark

   2011/3/1 Daniel Esteban Herrera Peña
  Continuing with the frequency   problem...

   Now from CentOS I checked the same design, it's the
  spectrometer from tutorial 3 which I change freq from
800   to 1000MHz and I also change the User IP
Clock Rate from   200 to 250MHz, the synthesis
stops in the same error, but   now I see that
the numbers are slight different:

 
--
  Constraint|Check
   | Worst Case |  Best Case | Timing |
Timing
|

|Slack   |
Achievable |
Errors |
Score
 
--
  * PERIOD analysis for net "tut3_adc/tut3_ad
| SETUP |-1.638ns|
  5.638ns| 110|   45473
c/adc_clk_dcm" derived from  NET "tut3_ad | HOLD|
 0.102ns||   0|
0
c/tut3_adc/adc_clk_buf" PERIOD = 4 ns HIG | |
|||
H 50% | |
|||

   I don't know what else I need to do! any insight will be
   greatly appreciated!

   Cheers,

 Daniel.

   On Fri, 25 Feb 2011 16:46:45 -0300, Daniel Esteban
 Herrera Peña
wrote:
Hi Henry,

 Thanks for your quick response, as you thought, I
indeed enter
 2000... in the meantime I digest how ADC works, I
tried to compile
 changing freq 800 to 1000 in the original design (no
   interleaving),
 and I receive this error:


 
-

Re: [casper] High clock freq timing error

2011-03-01 Thread Danny Price

Hey Daniel

Things start to get sticky when you go above 200MHz FPGA clock with that 
tute 3 spectrometer, so you might have to tweak some things under the 
hood to get it working at 250MHz. Have a look at this thread:

http://www.mail-archive.com/casper@lists.berkeley.edu/msg01804.html

As Mark said, have a look at the detailed timing report to try and track 
down the rogue blocks.


Also, make sure you're using an up-to-date git repository; Andrew made 
some useful changes to the pfb and adc blocks to make them behave nicer 
at higher frequencies (thanks Andrew!). In particular, these commits are 
a must:

http://casper.berkeley.edu/git/?p=mlib_devel/bwrc.git;a=commit;h=d81d7523efbbb7668ea04a4b3ce3ddc3107ad875
http://casper.berkeley.edu/git/?p=mlib_devel/bwrc.git;a=commit;h=37c90e2b98da3a48a4d3f7b67980fdd28b32a6ce

To summarize all this, to get the spectrometer working at 250MHz I would 
suggest:

* updating to the latest git repository
* deleting the PFB_FIR_REAL block and dragging in a new one from your 
newly updated library

* deleting the FFT block too, and adding in a new one
* changing to the settings mentioned here: 
http://www.mail-archive.com/casper@lists.berkeley.edu/msg01804.html


Hope that makes sense!

Cheers and good luck
Danny


On 01/03/2011 22:17, Mark Wagner wrote:

Hi Daniel,

From the Matlab command prompt, you can type dos('timingan') and then 
open the timing report ./XPS_ROACH_base/implementation/system.twx from 
the analyzer.  You'll see where the timing issues are occurring (i.e. 
negative slack).  You can then go back to your design and add 
registers or delays where appropriate to hopefully allow data to 
propagate in a reasonable time.  This takes up resources though, and 
can sometimes make things worse.  If you're unable to get the design 
to meet timing at this point, it may behoove you to use the floor 
planner.


Mark


2011/3/1 Daniel Esteban Herrera Peña >


Continuing with the frequency problem...

Now from CentOS I checked the same design, it's the spectrometer
from tutorial 3 which I change freq from 800 to 1000MHz and I also
change the User IP Clock Rate from 200 to 250MHz, the synthesis
stops in the same error, but now I see that the numbers are slight
different:



--
 Constraint|Check| Worst
Case |  Best Case | Timing |   Timing
   | |  
 Slack   | Achievable | Errors |Score


--
* PERIOD analysis for net "tut3_adc/tut3_ad | SETUP   |  
 -1.638ns| 5.638ns| 110|   45473
 c/adc_clk_dcm" derived from  NET "tut3_ad | HOLD|
0.102ns||   0|   0
 c/tut3_adc/adc_clk_buf" PERIOD = 4 ns HIG | |
   |||
 H 50% | |
   |||


I don't know what else I need to do! any insight will be greatly
appreciated!

Cheers,

Daniel.


On Fri, 25 Feb 2011 16:46:45 -0300, Daniel Esteban Herrera Peña
mailto:danherr...@udec.cl>> wrote:

Hi Henry,

Thanks for your quick response, as you thought, I indeed enter
2000... in the meantime I digest how ADC works, I tried to compile
changing freq 800 to 1000 in the original design (no
interleaving),
and I receive this error:



--
 Constraint|Check| Worst
Case |  Best Case | Timing |   Timing
   | |  
 Slack

| Achievable | Errors |Score


--
* PERIOD analysis for net "spec_1ghz_adc/sp | SETUP   |
-0.656ns| 4.656ns| 123|   31325
 ec_1ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
0.118ns||   0|   0
 T "spec_1ghz_adc/spec_1ghz_adc/adc_clk_bu | |
|||
 f" PERIOD = 4 ns HIGH 50% | |
|||


--
 TS_epb_clk = PERIOD TIMEGRP "epb_clk" 88  | SETUP   |
0.134ns|11.229ns|   0|   0
 MHz HIGH 50%  | HOLD|
0.360ns||   0|   0


-

Re: [casper] High clock freq timing error

2011-03-01 Thread Mark Wagner
Hi Daniel,

>From the Matlab command prompt, you can type dos('timingan') and then open
the timing report ./XPS_ROACH_base/implementation/system.twx from the
analyzer.  You'll see where the timing issues are occurring (i.e. negative
slack).  You can then go back to your design and add registers or delays
where appropriate to hopefully allow data to propagate in a reasonable time.
 This takes up resources though, and can sometimes make things worse.  If
you're unable to get the design to meet timing at this point, it may behoove
you to use the floor planner.

Mark


2011/3/1 Daniel Esteban Herrera Peña 

> Continuing with the frequency problem...
>
> Now from CentOS I checked the same design, it's the spectrometer from
> tutorial 3 which I change freq from 800 to 1000MHz and I also change the
> User IP Clock Rate from 200 to 250MHz, the synthesis stops in the same
> error, but now I see that the numbers are slight different:
>
>
>
> --
>  Constraint|Check| Worst Case |
>  Best Case | Timing |   Timing
>| |Slack   |
> Achievable | Errors |Score
>
> --
> * PERIOD analysis for net "tut3_adc/tut3_ad | SETUP   |-1.638ns|
>   5.638ns| 110|   45473
>  c/adc_clk_dcm" derived from  NET "tut3_ad | HOLD| 0.102ns|
>|   0|   0
>  c/tut3_adc/adc_clk_buf" PERIOD = 4 ns HIG | ||
>||
>  H 50% | ||
>||
>
> I don't know what else I need to do! any insight will be greatly
> appreciated!
>
> Cheers,
>
> Daniel.
>
>
> On Fri, 25 Feb 2011 16:46:45 -0300, Daniel Esteban Herrera Peña <
> danherr...@udec.cl> wrote:
>
>> Hi Henry,
>>
>> Thanks for your quick response, as you thought, I indeed enter
>> 2000... in the meantime I digest how ADC works, I tried to compile
>> changing freq 800 to 1000 in the original design (no interleaving),
>> and I receive this error:
>>
>>
>>
>> --
>>  Constraint|Check| Worst
>> Case |  Best Case | Timing |   Timing
>>| |Slack
>> | Achievable | Errors |Score
>>
>>
>> --
>> * PERIOD analysis for net "spec_1ghz_adc/sp | SETUP   |
>> -0.656ns| 4.656ns| 123|   31325
>>  ec_1ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
>> 0.118ns||   0|   0
>>  T "spec_1ghz_adc/spec_1ghz_adc/adc_clk_bu | |
>> |||
>>  f" PERIOD = 4 ns HIGH 50% | |
>> |||
>>
>>
>> --
>>  TS_epb_clk = PERIOD TIMEGRP "epb_clk" 88  | SETUP   |
>> 0.134ns|11.229ns|   0|   0
>>  MHz HIGH 50%  | HOLD|
>> 0.360ns||   0|   0
>>
>>
>> --
>>  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | MINLOWPULSE |
>> 1.000ns| 3.000ns|   0|   0
>>  buf" PERIOD = 4 ns HIGH 50%   | |
>> |||
>>
>>
>> --
>>  NET "epb_cs_n_IBUF" MAXDELAY = 4 ns   | MAXDELAY|
>> 2.366ns| 1.634ns|   0|   0
>>
>>
>> --
>>  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | N/A |
>> N/A| N/A| N/A| N/A
>>  buf" PERIOD = 4 ns HIGH 50%   | |
>> |||
>>
>>
>> --
>>
>> I see with this that I won't even be able to compile an interleaved
>> design, what else I can try?
>>
>> Thank you,
>>
>> Daniel H.
>>
>> On Fri, 25 Feb 2011 10:58:47 -0800, Henry Chen
>>  wrote:
>>
>>> Hi Daniel,
>>>
>>> It looks like you might have put 2000 into the "ADC clock rate"
>>> setting in the ADC yellow block. This will try to run the FPGA at
>>> 500MHz, which explains the timing error (it's very difficult
>>> to run the FPGA beyond 350MHz for a complex DSP design).
>>>
>>> I'm guessing you want to sample at 2GS/s, in which case you would put
>>> 1000 into the "ADC clock rate" box, and che

Re: [casper] High clock freq timing error

2011-03-01 Thread Daniel Esteban Herrera Peña

Continuing with the frequency problem...

Now from CentOS I checked the same design, it's the spectrometer from 
tutorial 3 which I change freq from 800 to 1000MHz and I also change the 
User IP Clock Rate from 200 to 250MHz, the synthesis stops in the same 
error, but now I see that the numbers are slight different:


--
  Constraint|Check| Worst Case 
|  Best Case | Timing |   Timing
| |Slack   
| Achievable | Errors |Score

--
* PERIOD analysis for net "tut3_adc/tut3_ad | SETUP   |
-1.638ns| 5.638ns| 110|   45473
  c/adc_clk_dcm" derived from  NET "tut3_ad | HOLD| 
0.102ns||   0|   0
  c/tut3_adc/adc_clk_buf" PERIOD = 4 ns HIG | |
|||
  H 50% | |
|||


I don't know what else I need to do! any insight will be greatly 
appreciated!


Cheers,

Daniel.

On Fri, 25 Feb 2011 16:46:45 -0300, Daniel Esteban Herrera Peña 
 wrote:

Hi Henry,

Thanks for your quick response, as you thought, I indeed enter
2000... in the meantime I digest how ADC works, I tried to compile
changing freq 800 to 1000 in the original design (no interleaving),
and I receive this error:


--
  Constraint|Check| Worst
Case |  Best Case | Timing |   Timing
| |Slack
| Achievable | Errors |Score

--
* PERIOD analysis for net "spec_1ghz_adc/sp | SETUP   |
-0.656ns| 4.656ns| 123|   31325
  ec_1ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
0.118ns||   0|   0
  T "spec_1ghz_adc/spec_1ghz_adc/adc_clk_bu | |
|||
  f" PERIOD = 4 ns HIGH 50% | |
|||

--
  TS_epb_clk = PERIOD TIMEGRP "epb_clk" 88  | SETUP   |
0.134ns|11.229ns|   0|   0
  MHz HIGH 50%  | HOLD|
0.360ns||   0|   0

--
  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | MINLOWPULSE |
1.000ns| 3.000ns|   0|   0
  buf" PERIOD = 4 ns HIGH 50%   | |
|||

--
  NET "epb_cs_n_IBUF" MAXDELAY = 4 ns   | MAXDELAY|
2.366ns| 1.634ns|   0|   0

--
  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | N/A |
N/A| N/A| N/A| N/A
  buf" PERIOD = 4 ns HIGH 50%   | |
|||

--

I see with this that I won't even be able to compile an interleaved
design, what else I can try?

Thank you,

Daniel H.

On Fri, 25 Feb 2011 10:58:47 -0800, Henry Chen
 wrote:

Hi Daniel,

It looks like you might have put 2000 into the "ADC clock rate"
setting in the ADC yellow block. This will try to run the FPGA at
500MHz, which explains the timing error (it's very difficult
to run the FPGA beyond 350MHz for a complex DSP design).

I'm guessing you want to sample at 2GS/s, in which case you would 
put
1000 into the "ADC clock rate" box, and check the "ADC interleave 
mode"
box, which will give you the effective 2GHz sampling rate. It will 
also

run the FPGA at a much more manageable 250MHz.

What you put into the "ADC clock rate" box indicates the frequency 
of

the actual sampling clock signal you would connect to the ADC board,
rather than the effective sampling rate. For the iADC it can't go 
much

beyond 1GHz.

Sorry that it's kind of confusing!

Thanks,
Henry

On 2/25/2011 7:56 AM, Daniel Esteban Herrera Peña wrote:

Hi everyone,
I could sucessfully synthesize the spectrometer example, now I 
tried to change input frequency from the original 800MHz to 2000MHz 
using interleave mode, in order to avoid major changes in the design, 
I connected o0, o2, o4 and o6 in the pfb block (putting a terminator 
on the rest on the ADC outputs), after some minutes compiling a 
timing error appears, v

Re: [casper] High clock freq timing error

2011-02-25 Thread Daniel Esteban Herrera Peña

Hi Henry,

Thanks for your quick response, as you thought, I indeed enter 2000... 
in the meantime I digest how ADC works, I tried to compile changing freq 
800 to 1000 in the original design (no interleaving), and I receive this 
error:


--
  Constraint|Check| Worst Case 
|  Best Case | Timing |   Timing
| |Slack   
| Achievable | Errors |Score

--
* PERIOD analysis for net "spec_1ghz_adc/sp | SETUP   |
-0.656ns| 4.656ns| 123|   31325
  ec_1ghz_adc/adc_clk_dcm" derived from  NE | HOLD| 
0.118ns||   0|   0
  T "spec_1ghz_adc/spec_1ghz_adc/adc_clk_bu | |
|||
  f" PERIOD = 4 ns HIGH 50% | |
|||

--
  TS_epb_clk = PERIOD TIMEGRP "epb_clk" 88  | SETUP   | 
0.134ns|11.229ns|   0|   0
  MHz HIGH 50%  | HOLD| 
0.360ns||   0|   0

--
  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | MINLOWPULSE | 
1.000ns| 3.000ns|   0|   0
  buf" PERIOD = 4 ns HIGH 50%   | |
|||

--
  NET "epb_cs_n_IBUF" MAXDELAY = 4 ns   | MAXDELAY| 
2.366ns| 1.634ns|   0|   0

--
  NET "spec_1ghz_adc/spec_1ghz_adc/adc_clk_ | N/A | 
N/A| N/A| N/A| N/A
  buf" PERIOD = 4 ns HIGH 50%   | |
|||

--

I see with this that I won't even be able to compile an interleaved 
design, what else I can try?


Thank you,

Daniel H.

On Fri, 25 Feb 2011 10:58:47 -0800, Henry Chen 
 wrote:

Hi Daniel,

It looks like you might have put 2000 into the "ADC clock rate"
setting in the ADC yellow block. This will try to run the FPGA at
500MHz, which explains the timing error (it's very difficult
to run the FPGA beyond 350MHz for a complex DSP design).

I'm guessing you want to sample at 2GS/s, in which case you would put
1000 into the "ADC clock rate" box, and check the "ADC interleave 
mode"
box, which will give you the effective 2GHz sampling rate. It will 
also

run the FPGA at a much more manageable 250MHz.

What you put into the "ADC clock rate" box indicates the frequency of
the actual sampling clock signal you would connect to the ADC board,
rather than the effective sampling rate. For the iADC it can't go 
much

beyond 1GHz.

Sorry that it's kind of confusing!

Thanks,
Henry

On 2/25/2011 7:56 AM, Daniel Esteban Herrera Peña wrote:

Hi everyone,
I could sucessfully synthesize the spectrometer example, now I tried 
to change input frequency from the original 800MHz to 2000MHz using 
interleave mode, in order to avoid major changes in the design, I 
connected o0, o2, o4 and o6 in the pfb block (putting a terminator on 
the rest on the ADC outputs), after some minutes compiling a timing 
error appears, very similar that I had before but because of a low 
freq input clock, this time I'm trying to work with a higher value 
than design, the error is as follow:

Asterisk (*) preceding a constraint indicates it was not met.
   This may be due to a setup or hold violation.

--
Constraint|Check| Worst Case 
|  Best Case | Timing |   Timing
| |Slack 
 | Achievable | Errors |Score


--
* PERIOD analysis for net "spec_2ghz_adc/sp | SETUP   |
-0.618ns| 2.618ns|1949|  324926
  ec_2ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
-0.179ns||2718|  251622
  T "spec_2ghz_adc/spec_2ghz_adc/adc_clk_bu | MINPERIOD   |
-0.222ns| 2.222ns| 393|   87245
  f" PERIOD = 2 ns HIGH 50%  duty cycle cor | MINLOWPULSE | 
0.000ns| 2.000ns|   0|   0
  rected to 2 nS  HIGH 1000 pS  | MINHIGHPULSE| 
0.000ns| 2.000ns|   0|   0


-

Re: [casper] High clock freq timing error

2011-02-25 Thread Henry Chen

Hi Daniel,

It looks like you might have put 2000 into the "ADC clock rate"
setting in the ADC yellow block. This will try to run the FPGA at
500MHz, which explains the timing error (it's very difficult
to run the FPGA beyond 350MHz for a complex DSP design).

I'm guessing you want to sample at 2GS/s, in which case you would put
1000 into the "ADC clock rate" box, and check the "ADC interleave mode"
box, which will give you the effective 2GHz sampling rate. It will also
run the FPGA at a much more manageable 250MHz.

What you put into the "ADC clock rate" box indicates the frequency of
the actual sampling clock signal you would connect to the ADC board,
rather than the effective sampling rate. For the iADC it can't go much
beyond 1GHz.

Sorry that it's kind of confusing!

Thanks,
Henry

On 2/25/2011 7:56 AM, Daniel Esteban Herrera Peña wrote:

Hi everyone,

I could sucessfully synthesize the spectrometer example, now I tried to 
change input frequency from the original 800MHz to 2000MHz using 
interleave mode, in order to avoid major changes in the design, I 
connected o0, o2, o4 and o6 in the pfb block (putting a terminator on 
the rest on the ADC outputs), after some minutes compiling a timing 
error appears, very similar that I had before but because of a low freq 
input clock, this time I'm trying to work with a higher value than 
design, the error is as follow:


Asterisk (*) preceding a constraint indicates it was not met.
   This may be due to a setup or hold violation.

-- 

  Constraint|Check| Worst Case 
|  Best Case | Timing |   Timing
| |Slack   | 
Achievable | Errors |Score
-- 

* PERIOD analysis for net "spec_2ghz_adc/sp | SETUP   |
-0.618ns| 2.618ns|1949|  324926
  ec_2ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
-0.179ns||2718|  251622
  T "spec_2ghz_adc/spec_2ghz_adc/adc_clk_bu | MINPERIOD   |
-0.222ns| 2.222ns| 393|   87245
  f" PERIOD = 2 ns HIGH 50%  duty cycle cor | MINLOWPULSE | 
0.000ns| 2.000ns|   0|   0
  rected to 2 nS  HIGH 1000 pS  | MINHIGHPULSE| 
0.000ns| 2.000ns|   0|   0
-- 

* NET "spec_2ghz_adc/spec_2ghz_adc/adc_clk_ | MINPERIOD   |
-0.221ns| 2.221ns|   1| 221
  buf" PERIOD = 2 ns HIGH 50%   | |
|||
-- 



This same adc_clk_buf and adc_clk_dcm gave me some headaches before with 
low clock frequency, but that time David George advice me to change in 
xps_lib/XPS_ROACH_base/pcores/adc_interface_v1_01_a/hdl/vhdl/adc_interface.vhd 
variables FS_FREQUENCY_MODE and DLL_FREQUENCY_MODE from HIGH to LOW. Now 
those variables are set in HIGH, so how can I make ADC/ROACH happy with 
this 2GHz input clock?


Cheers,

Daniel H.





[casper] High clock freq timing error

2011-02-25 Thread Daniel Esteban Herrera Peña

Hi everyone,

I could sucessfully synthesize the spectrometer example, now I tried to 
change input frequency from the original 800MHz to 2000MHz using 
interleave mode, in order to avoid major changes in the design, I 
connected o0, o2, o4 and o6 in the pfb block (putting a terminator on 
the rest on the ADC outputs), after some minutes compiling a timing 
error appears, very similar that I had before but because of a low freq 
input clock, this time I'm trying to work with a higher value than 
design, the error is as follow:


Asterisk (*) preceding a constraint indicates it was not met.
   This may be due to a setup or hold violation.

--
  Constraint|Check| Worst Case 
|  Best Case | Timing |   Timing
| |Slack   
| Achievable | Errors |Score

--
* PERIOD analysis for net "spec_2ghz_adc/sp | SETUP   |
-0.618ns| 2.618ns|1949|  324926
  ec_2ghz_adc/adc_clk_dcm" derived from  NE | HOLD|
-0.179ns||2718|  251622
  T "spec_2ghz_adc/spec_2ghz_adc/adc_clk_bu | MINPERIOD   |
-0.222ns| 2.222ns| 393|   87245
  f" PERIOD = 2 ns HIGH 50%  duty cycle cor | MINLOWPULSE | 
0.000ns| 2.000ns|   0|   0
  rected to 2 nS  HIGH 1000 pS  | MINHIGHPULSE| 
0.000ns| 2.000ns|   0|   0

--
* NET "spec_2ghz_adc/spec_2ghz_adc/adc_clk_ | MINPERIOD   |
-0.221ns| 2.221ns|   1| 221
  buf" PERIOD = 2 ns HIGH 50%   | |
|||

--

This same adc_clk_buf and adc_clk_dcm gave me some headaches before 
with low clock frequency, but that time David George advice me to change 
in 
xps_lib/XPS_ROACH_base/pcores/adc_interface_v1_01_a/hdl/vhdl/adc_interface.vhd 
variables FS_FREQUENCY_MODE and DLL_FREQUENCY_MODE from HIGH to LOW. 
Now those variables are set in HIGH, so how can I make ADC/ROACH happy 
with this 2GHz input clock?


Cheers,

Daniel H.