2008/6/16 Timothy Normand Miller <[EMAIL PROTECTED]>: > On Mon, Jun 16, 2008 at 8:47 AM, Kenneth Ostby <[EMAIL PROTECTED]> wrote: >> Timothy Normand Miller: >>>On Fri, Jun 13, 2008 at 6:54 PM, Jared Putnam <[EMAIL PROTECTED]> wrote: >>>> --- On Fri, 6/13/08, Timothy Normand Miller <[EMAIL PROTECTED]> wrote: >>>>> These may be nothing, but they should be investigated: >>>> [unused pins] >>>> >>>> Did you ever get a tool put together to ensure that all module >>>> instatiations use the right number of wires for each port? >>> >>>Not sure. I think someone wrote one in Perl or was going to, but I >>>can't remember. That would be a good sanity check. >> >> I did write a simple one in perl quite some time ago, however, when I >> saw that the icarus had a switch for it, I discontinued the development >> of it. Atm. I can't remember the name of the switch, but should be >> easy to find it in the icarus man page. > > Well, anyhow, I've managed to fix all the warnings that are actually > problems. Also, there were some problems with entries in the > constraints file not finding the nets they were associated with. > Turns out that some signals were getting ripped out because they were > duplicates of other signals. I put in some metacomments to force them > not to be ripped out, and voila. > > So, wrt the XP10, we still are stuck on the PCI clock skew issue, and > for the S3, we're blowing the memory clock period constraint. The > latter is entirely an internal problem. I have four different logic > blocks trying to pull from a single fifo, so when it's time to > dequeue, I have to make sure only to dequeue when the intended target > is ready to get the data. That results in a loop from fifo out data > back into the dequeue signal. The simplest fix is to have four > separate command fifos, but that's a massive waste of logic area. But > then again, so are most of the the other options. > >
Can't you use a pipeline ? Duplicate only the last fifo stage ? Or sometime, in a FSM, you could create a specific register for the bit in the critical path. So you avoid any output decoding logic. Regards, Nicolas _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
