Hi Louis, The problem is probably that the DCM/MMCM has various configuration parameters which have default values for the clock speeds most commonly used for CASPER designs. To run at lower speeds, you'll need to tweak these values. I thought they can be found in the XPS_ROACH_base/data/system.ucf file that is generated for your design, but I'm not seeing it there right now. Perhaps someone else can guide you to the location of the parameters if you don't find them first. Glenn
On Mon, Jan 23, 2012 at 2:46 PM, Louis Dartez <louisdar...@gmail.com> wrote: > Hello fellow CASPERites, > > > I've been trying to modify the wideband spectrometer tutorial to > have the MSSGE block clock rate set to 50 MHz and, following the 4 to 1 > rule, the ADC running at 200 MHz. Simulink complains about timing errors > when I try to do this. Is there another parameter that I'm forgetting about > and need to change? Or is there some lower limit for the ROACH clock rate? > I figured that as long as the adc is clocked at 4x the roach rate then I > should be able to lower both of them as long as I keep them at the same > ratio. > > Any thoughts? > > -- > -- Louis Dartez > (956) 372-5812 > Arecibo Remote Command Center Scholar > Center for Advanced Radio Astronomy > University of Texas at Brownsville > > >
