Hi Zhiwei, Are you certain the design met timing at 250MHz? Have you checked the timing report? Does the garbage output begin sharply at 800MHz? How fast are you reading out spectra?
(Sorry for lots of questions and no answers =) ) - Andrew On 8/12/09 11:36 AM, "Zhiwei Liu" <[email protected]> wrote: > Hello, > > Recently I just ported my spectrometer design from ibob to roach. The > spectrometer is 500 MHz bandwidth (ADC clock: 1000 MHz). > > The simulation and compiling is successful, but when I run it with roach, I > can only get the meaningful spectrum at the ADC clock under 800 MHz. > > When the ADC clock is large than 800 MHz, the spectrum output is just noise. > The same design of ibob version can run at FPGA clock 250 MHz without any > problem. > > Does anyone have the similar problem? Or is there anyone have ever run the > roach design with FPGA clock larger than 250 MHz.
