You cannot have a block with 0 inputs or 0 outputs from the HDL perspective. You will always have at least 1 input and 1 output. You can tie off the unused input or output though. Also, in your GRC XML, you can choose not to declare the output or input. Check out uhd_rfnoc_siggen.xml, which works just fine as a 0-input 1-output block even though siggen.xml has a "dump" input declared.
On Wed, Aug 1, 2018 at 1:40 AM, Jason Matusiak <ja...@gardettoengineering.com> wrote: > What I don't understand is, why is the null sink able to have one input and > no outputs? I would think that it would suffer the same issues that a 2-in > 1-out block would have. > > I tried to understand the noc_block_null_source_sink.v, but I didn't really > see how to use it as a sink only. I was going to create my own, but then I > had the question from above. > > I am a little worried about the constraints that the block-to-block > messaging has, so I was going to change my block to a 2-in 1-out block, but > then remembered those issues. Then my answer was to make it 2-in 2-out > (like it is now), but connected a null sink to the unneeded output. > > Any words of wisdom? > > > > > --------- Original Message --------- > Subject: Re: [USRP-users] noc_block_null_source_sink module > From: "Jon Pendlum" <jon.pend...@gmail.com> > Date: 7/30/18 10:49 pm > To: "Jason Matusiak" <ja...@gardettoengineering.com> > Cc: "Ettus Mail List" <usrp-users@lists.ettus.com> > > Hey Jason, > > The block is functionally complete, in fact I think it was the first > block ever made. There is a UHD C++ example, > rfnoc_nullsource_ce_rx.cpp, that uses it. A block controller and GRC > xml for GNU Radio needs to be created though. > > Jonathon > > On Wed, Jul 18, 2018 at 4:38 AM, Jason Matusiak via USRP-users > <usrp-users@lists.ettus.com> wrote: >> I was having trouble finding information on this block. I could see its >> usefulness in an application I am looking into, but I wasn't sure how >> complete the block was (I don't really see anything using it, nor a GRC >> xml >> file for it). >> >> Thanks >> >> _______________________________________________ >> USRP-users mailing list >> USRP-users@lists.ettus.com >> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
