I found my mistake. I did not have feedback input and output ports of the mmcm (CLKFBOUT,CLKFBIN) connected correctly.
Matt On Tue, Apr 19, 2016 at 12:10 PM, Matt Strader <[email protected]> wrote: > Hello Casperites, > > I am working on a roach2 yellow block for a new 12bit, 2.0 Gsps ADC/DAC > board designed at Fermilab. I am having trouble with clocks. The ADC/DAC > board is providing me with a 500 MHz clock over a particular zdok pair. My > yellow block takes this into an mmcm and divides it down to 250 MHz to be > used as the fabric clock. > > When testing it, I set the adc/dac clock running, then program the > roach2. When I call KatcpFpga.estimate_fpga_clock() it returns 167 MHz > instead of the expected 250 MHz. > > I have attached what I think are the relevant snippets from my yellow > block. The rest of it can be found at > https://github.com/mstrader/mlib_devel > Any ideas what could be the problem? > > Thanks, > Matt Strader >
