11-22-2019 08:26 AM
In forum posts such as this one, it is reported that the Utility Buffer should support IOBUF as of v2.1. I can even see it in the change log. But when I place a Utility Buffer in my block diagram, the name has a "ds" in it and all of the options are for differential IO buffers. What am I doing wrong? I need a normal IOBUF, not IOBUFDS.
11-22-2019 08:36 AM
11-22-2019 09:59 AM
I'm using Vivado 2019.1 with a block diagram flow. In IP Catalog, the IP says it's v2.1, Rev. 19.
I want to use the utility buffer to handle a top-level port that tristates. As far as I know my only other option is to wrap an IOBUF in an RTL block and put that in. Is there a better way?
11-23-2019 02:24 AM
I dont know block diagram flow that well,
I just dont use it, and dont have it here on the tablet,
As I rember you only need the util buffer if your using differential outputs
single ended outputs are "just connected" tot he top level, and IO buffers are instantiated,
That does imply that there is a tri state bufer some where in the IP package,
Sorry, hope some oen else can be of more help
11-25-2019 05:15 AM
What we found is that when we try to infer a tristate buffer in the IP (e.g. with an assign of 1'bz), it doesn't work. Perhaps we have to explicitly instantiate an OBUF in the IP?