Hi Dan, The FPGA is clocked at 200 MHz. I used the 3 Gs/s ADC yellow block running at 1600 MHz feeding a 8 input wideband FFT. The timing errors were in the FFT.
Laura On Thu, May 13, 2010 at 10:58 PM, Dan Werthimer <[email protected]> wrote: > > hi laura, > > are you trying to clock your FGPA at 200 or 400 MHz? > > if you configure the ADC yellow block to input 4 samples per clock, > and sampling at 1600 Msps, then you will need to clock your > fpga at 400 MHz, which is pretty near impossible for virtex 5 > and you'll get lots of timing errors. > > if you configure the yellow block to input 8 samples per clock, > and sampling at 1600 Msps, then the FGPA is clocking at 200 MHz, > and routing and timing should work. > > best wishes, > > dan > > On 5/13/2010 6:46 PM, Laura Spitler wrote: >> >> Hi everyone, >> >> Does anyone have a sense of whether a dual polarization, 800 MHz >> spectrometer with ~2k channels would fit into a ROACH? I have a test >> design using the ADC083000 and and two small wideband FFTs. It seems >> to work in terms of utilization, but I get a crazy number of timing >> errors. >> Has anyone successfully built anything like this? >> >> Thanks, >> Laura >> >> > > >
