Re: [casper] QDR ROACH2: clocking at 145 MHz

Hi Jack I'm using the latest mlib_devel on the ska-sa git repo (commit 0d5c582), and I built against it, but with the changes of commit 72d879c. JP On Sat, May 23, 2015 at 2:20 AM, Jack Hickish jackhick...@gmail.com wrote: Hi JP, What mlib_devel are you using? Did you actually build against

Re: [casper] QDR ROACH2: clocking at 145 MHz

Hey Guys, Just to give you a bit of history on this issue. Normally the QDRs have take a clock input and then return this clock aligned with the data out. The QDRs on ROACH 2 were routed without this clock and with out th data valid line to save pins on the FPGA. This would have been ok if the

Re: [casper] QDR ROACH2: clocking at 145 MHz

Hi Andrew Thanks for your reply. Can this also be an impedance matching issue, where at lower frequencies the 50 ohm match is bad and there are reflections? When you talk about pipeline length are you referring to the 10 clock cycle latency that has been hard-coded? Is there a systematic way to

Re: [casper] QDR ROACH2: clocking at 145 MHz

Hi JP, What mlib_devel are you using? Did you actually build against commit 72d879c? I noticed you emailed a link to my repository which I specifically tweaked for my higher (312MHz) work, which I'm sure breaks *everything* at 145. Cheers, Jack On Fri, 22 May 2015 at 06:41 Juan-Pierre Jansen

[casper] QDR ROACH2: clocking at 145 MHz

Hi all, I'm trying to get the QDR on the ROACH-2 to work reliably at a clock speed of a 145 MHz. I'm assuming this is possible, since it has been pointed out in an earlier message http://www.mail-archive.com/casper%40lists.berkeley.edu/msg05736.html that the QDR should work above 120 MHz? I'm