Oh, that's clear!  I followed it and got the design compiled successfully
in Simulink. Thanks Jack!

Best,

Weiwei


On Wed, Jan 15, 2014 at 12:35 PM, Jack Hickish <jackhick...@gmail.com>wrote:

> Hi Weiwei,
>
> I'll leave it up to Rurik to merge or not the changes into
> sma-wideband, but in the meantime, the changes (along with LOTS of
> other modifications to other parts of the library) are in my repo at
> https://github.com/jack-h/mlib_devel
>
> Alternatively, if you've got the latest mlib_devel from sma-wideband,
> you can apply the patch I emailed using the command (run within the
> repository)
>
> git apply /path/to/adc5g-mmcm.patch
>
> Cheers,
> Jack
>
> On 15 January 2014 20:24, Weiwei Sun <su...@uw.edu> wrote:
> > Hi Jack and Rurik,
> >
> > I'm very excited to hear that the adc could run at exact 5GSPS mode (2
> > channels, demux 1:1) . I'd like to follow the modification, but the vhdl
> is
> > something that I'm not familiar. I wonder if it is possible that the
> module
> > could be merged into the sma-wideband github, or help with some more
> details
> > to instruct me to make the modification. That would be a BIG help for my
> > project.  Thanks!
> >
> > Best,
> >
> > Weiwei
> >
> >
> > On Wed, Jan 15, 2014 at 9:53 AM, Jack Hickish <jackhick...@gmail.com>
> wrote:
> >>
> >> On 15 January 2014 16:28, Primiani, Rurik <rprimi...@cfa.harvard.edu>
> >> wrote:
> >> > Hi Jack,
> >> >
> >> > Great work! The oversample mode is not something I realized existed!
> >>
> >> Me neither -- I eventually stumbled across it in the SelectIO
> >> Resources guide. (Where the order of the SERDES module outputs are
> >> documented wrongly, just for extra fun)
> >>
> >> >
> >> > Previously when we've been able to get the tools to use HIGH bandwidth
> >> > mode we could get away with just shifting the MMCM clock phase to
> >> > remove glitches on the interface (i.e. no IODELAY adjustments). Have
> >> > you tried just doing that?
> >>
> >> I've run your calibration routine to look at the glitches vs. phase
> >> values and it seems to find reasonably wide glitchless regions. But I
> >> find the differences between the "slowest" and "fastest" bits from the
> >> ADC to be around 4 IODELAY taps (312ps), so it seemed worth doing a
> >> per-bit calibration anyway.
> >> With IODELAY calibration only (without bothering with the MMCM phase)
> >> so far I haven't had any glitches in 2 hours of running. Strangely,
> >> when I ran the MMCM phasing calibration after IODELAY cal, things got
> >> worse, but I've been wildly hacking software, so there's a very
> >> reasonable chance I've broken something. I'll look into this after
> >> I've let my current glitch counting test run for a bit longer.
> >>
> >>
> >> >
> >> > I'd like to merge your change into sma-wideband, could you perhaps
> >> > send me a Github pull request?
> >>
> >> Our git repos seem to have diverged quite a lot, but I've attached a
> >> patch to peruse/edit/merge at your leisure. Obviously, YMMV :)
> >>
> >> Cheers,
> >> Jack
> >>
> >>
> >> >
> >> > Thanks!
> >> > Rurik
> >> >
> >> > On Wed, Jan 15, 2014 at 7:51 AM, Jack Hickish <jackhick...@gmail.com>
> >> > wrote:
> >> >> Hi Ross,
> >> >>
> >> >> Thanks for the info -- I've actually got a 5 Gsps ROACH2 (demux 1:1)
> >> >> pocket correlator compiled, and the final piece of the puzzle was
> >> >> getting the ADCs running properly (I only got hold of the hardware
> >> >> relatively recently). But it's always reassuring to know someone else
> >> >> is using a similar system with success!
> >> >>
> >> >> For anyone that's interested, I think I may have solved my problem. I
> >> >> changed the adc interface to use SERDES blocks in oversampling mode,
> >> >> which allowed me to dispense with the high frequency MMCM output.
> >> >> Without this troublesome output, the MMCM can be set into high
> >> >> bandwidth mode and the data capture seems to perform much more
> >> >> happily.
> >> >> After this mod, and setting the IODELAY blocks appropriately, the ADC
> >> >> appears to be capturing data happily without any problems....
> >> >>
> >> >> Cheers,
> >> >>
> >> >> Jack
> >> >>
> >> >> On 14 January 2014 18:18, Ross Williamson
> >> >> <rwilliam...@astro.caltech.edu> wrote:
> >> >>> Hi Jack,
> >> >>>
> >> >>> Not sure this helps as I'm using two DMUX 2:1 at 4GSPS as a
> correlator
> >> >>> on a ROACH-1.  The only think I would say is that I've put a fair
> >> >>> amount of effort in planahead to try and get 5GSPS. I'm sure it
> could
> >> >>> be done and I've thought I've got close a number of times but in the
> >> >>> end I've just eaten that 500MHz of BW as too much effort for the
> >> >>> little gain it gives in receiver noise.  I would say that on a
> >> >>> Roach-1, two boards at 5GSPS (4-bit) works fine if you are just
> >> >>> dumping data to a snapshot.  I believe a ROACH-2 is  harder to reach
> >> >>> timing.
> >> >>>
> >> >>> Ross
> >> >>>
> >> >>> On Tue, Jan 14, 2014 at 8:11 AM, Jack Hickish <
> jackhick...@gmail.com>
> >> >>> wrote:
> >> >>>> Hi all,
> >> >>>>
> >> >>>> Like Weiwei, I'm trying to use the ADC5g at 5 Gsps. I've played
> with
> >> >>>> a
> >> >>>> simple ADC to snap model, and (as Rurik warned) getting reliable
> data
> >> >>>> capturing is difficult at this speed. I've tried per-bit
> calibration
> >> >>>> of input data streams via IODELAYs in conjunction with
> phase-shifting
> >> >>>> of the sampling clock, but can't seem to achieve glitchless data
> >> >>>> capture for any reasonable length of time.
> >> >>>>
> >> >>>> In the email I'm replying to, Rurik suggests a number of ways
> around
> >> >>>> this problem, but before I opt for forcing an unsupported MMCM mode
> >> >>>> by
> >> >>>> compiling and running at different speeds, I thought a final
> >> >>>> desperate
> >> >>>> plea for any advice on the maillist might be worthwhile. If anyone
> >> >>>> has
> >> >>>> any words of wisdom, I'd be excessively grateful to hear from them.
> >> >>>>
> >> >>>> Cheers,
> >> >>>>
> >> >>>> Jack
> >> >>>>
> >> >>>> On 6 November 2013 16:31, Primiani, Rurik <
> rprimi...@cfa.harvard.edu>
> >> >>>> wrote:
> >> >>>>> Hi Weiwei,
> >> >>>>>
> >> >>>>> Generally the sma-wideband/mlib_devel has the most recent changes
> to
> >> >>>>> the ADC5g yellow block, please use the latest commit of that repo
> >> >>>>> (at
> >> >>>>> this moment it is 2c80cb2).
> >> >>>>>
> >> >>>>> The problem your are seeing is related to a change that was
> >> >>>>> introduced
> >> >>>>> in the Xilinx tools (I believe from version 11 to 12) that
> increased
> >> >>>>> the minimum frequency of the Virtex-6 MMCM's PFD to 135 MHz from
> 125
> >> >>>>> MHz in HIGH bandwidth mode. This made it no longer possible to
> clock
> >> >>>>> the fabric from an ADC5g running at >4800 Msps using an MMCM in
> HIGH
> >> >>>>> bandwidth mode.
> >> >>>>>
> >> >>>>> There are a few options for moving forward (ordered by ease of
> >> >>>>> implementation):
> >> >>>>>
> >> >>>>> 1. Clock the ADC below (and not including) 2400 MHz
> >> >>>>> 2. Change MMCM from HIGH to LOW bandwidth mode
> >> >>>>> 3. Compile your design with the ADC clocked above (and not
> >> >>>>> including)
> >> >>>>> 5400 MHz, but actually run it at 5 GHz
> >> >>>>> 4. Force the Xilinx tools to allow the PFD to run at 125 MHz in
> HIGH
> >> >>>>> bandwidth mode
> >> >>>>> 5. Compile your design using the Xilinx 11 tools
> >> >>>>>
> >> >>>>> If you don't need to sample at exactly 5 Gsps then option 1 is the
> >> >>>>> optimal solution. If 5 Gsps is critical then you can go with
> options
> >> >>>>> 2
> >> >>>>> or 3. Option 2 has non-ideal clock-to-out timing and may cause
> >> >>>>> problems when trying to calibrate out jitter due to the data
> >> >>>>> capturing. Option 3 may cause timing problems since your fabric
> >> >>>>> clock
> >> >>>>> will run at >337.5 MHz. I have not found a way to implement
> option 4
> >> >>>>> but I can't see why this shouldn't be possible. Finally option 5
> may
> >> >>>>> or may not be useful to you.
> >> >>>>>
> >> >>>>> The SMA wideband correlator runs its ADCs below 4800 Msps. However
> >> >>>>> we
> >> >>>>> have bitcodes that we use to characterize the ADC that run at 5
> Gsps
> >> >>>>> and which have low resource utilization. For what it's worth we
> used
> >> >>>>> option 3 to get around this issue and this appears to work for us.
> >> >>>>> Whatever reason Xilinx had for changing the minimum PFD frequency
> to
> >> >>>>> 135 MHz does not seem to cause problems for us.
> >> >>>>>
> >> >>>>> Hope this helps,
> >> >>>>> Rurik
> >> >>>>>
> >> >>>>>
> >> >>>>>
> >> >>>>> On Wed, Nov 6, 2013 at 2:29 AM, Weiwei Sun <su...@uw.edu> wrote:
> >> >>>>>> I tried the casper-astro, ska-sa, sma-wideband. None of them
> seemly
> >> >>>>>> works.
> >> >>>>>>
> >> >>>>>> Weiwei
> >> >>>>>>
> >> >>>>>>
> >> >>>>>> On Tue, Nov 5, 2013 at 10:20 PM, Primiani, Rurik
> >> >>>>>> <rprimi...@cfa.harvard.edu>
> >> >>>>>> wrote:
> >> >>>>>>>
> >> >>>>>>> Hi,
> >> >>>>>>>
> >> >>>>>>> Which version of mlib_devel are you using?
> >> >>>>>>>
> >> >>>>>>> Rurik
> >> >>>>>>>
> >> >>>>>>> On Tue, Nov 5, 2013 at 11:16 PM, Weiwei Sun <su...@uw.edu>
> wrote:
> >> >>>>>>> > Hi,
> >> >>>>>>> >
> >> >>>>>>> > I have trouble to compile the adc clock rate of asiaa_adc5g
> >> >>>>>>> > block at
> >> >>>>>>> > 2500MHz.
> >> >>>>>>> > Block parameter: two-channel, ZDOK0, demux 1:1 .
> >> >>>>>>> > System: roach2, clock source:adc0_clk, clock rate: 312.5MHz)
> >> >>>>>>> >
> >> >>>>>>> > The error is as follows:
> >> >>>>>>> >
> >> >>>>>>> > Creating block object: xps_adc5g
> >> >>>>>>> > Problem with block: lab_test_adv5/asiaa_adc5g1
> >> >>>>>>> > : An optimum PLL solution is not available!
> >> >>>>>>> > Backtrace 1: xps_adc5g:175
> >> >>>>>>> > Backtrace 2: gen_xps_files:229
> >> >>>>>>> > Backtrace 3: run_Callback:149
> >> >>>>>>> > Backtrace 4: casper_xps:82
> >> >>>>>>> > Backtrace 5:
> >> >>>>>>> >
> >> >>>>>>> >
> >> >>>>>>> >
> @(hObject,eventdata)casper_xps('run_Callback',hObject,eventdata,guidata(hObject)):0
> >> >>>>>>> > Error using gen_xps_files (line 242)
> >> >>>>>>> > Error found during Object creation.
> >> >>>>>>> >
> >> >>>>>>> > There are a bunch of frequency justification in the
> xps_adc5g.m
> >> >>>>>>> > that I
> >> >>>>>>> > just
> >> >>>>>>> > can't understand.  Could some one give me some suggestions on
> >> >>>>>>> > the error
> >> >>>>>>> > or
> >> >>>>>>> > the codes? Does it mean that the 5G adc can't run at 2.5GHz?
> >> >>>>>>> >
> >> >>>>>>> > Any help or suggestions are very appreciated!
> >> >>>>>>> >
> >> >>>>>>> > Weiwei
> >> >>>>>>> >
> >> >>>>>>> >
> >> >>>>>>> >
> >> >>>>>>> >
> >> >>>>>>
> >> >>>>>>
> >> >>>>>
> >> >>>>
> >> >>>
> >> >>>
> >> >>>
> >> >>> --
> >> >>> Ross Williamson
> >> >>> Research Scientist - Sub-mm Group
> >> >>> California Institute of Technology
> >> >>> 626-395-2647 (office)
> >> >>> 312-504-3051 (Cell)
> >> >>
> >
> >
>

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