If I remember correctly, the SMA inputs are not normally run through a DCM, they're just IO pins (I could be wrong about this..). Specifics on how to make a yellow block are on the wiki: https://casper.berkeley.edu/wiki/How_to_make_a_"yellow"_ block. Assuming your block is named 'newblock':
0) Sacrifice a goat to the EDK gods so that they will allow you to complete in a reasonable amount of time. 1) Edit xps_library/@xps_newblock/xps_newblock.m to have the SMA input as an input pin and the GPIO pin as an output pin. Look through other yellowblocks in the lines which modify the ext_ports struct for the right pins. Billy's modification is probably a good starting point 2) Use verilog/vhdl to put the SMA clock through a DCM & drive the output GPIO pin. This part should be pretty straightforward if you copy the instantiation from reference documentation -Suraj On Fri, Aug 26, 2011 at 9:15 PM, William Mallard <w...@llard.net> wrote: > Jon Losh wrote: > > So I'm interested in taking in a signal from one of the dedicated > > SMA clock inputs on the roach, running it through the DCM, and then > > out of the GPIO SMA. I specifically want the DCM because I can then > > actually lock multiple outputs together. Within the casper toolflow, > > there doesn't seem to be any access to these clock inputs besides as > > clock sources for the roach. > > > > From what I understand, I either need to figure out how to make a > > yellow block to access these inputs or splice in some verilog of my > > own. The verilog part seems somewhat inevitable, as it's really > > unclear how I give the DCM directives otherwise. Any ideas on how to > > go about doing this? > > Hi Jon, > > I modified the GPIO block to provide the option of using the aux_clk > SMAs as inputs. Check commit ccc4f9df in the bwrc fork for details. > > I'm not sure how you'd route this to the DCM, though. Sounds verilogy. > > Billy > >
