On Thu, Mar 27, 2008 at 06:36:38PM -0400, DJ Delorie wrote: > > ATX motherboard (or any pc motherboard shape, really, like micro-atx > or some laptop). PCI/PCIe slots, ISA slots, standard connectors, > SDRAM - whatever. > > A huge FPGA in the middle. [...]
My understanding is that with the GHz busses on modern mobos you need to pay serious attention to matching trace lengths and impedances exactly for the different lines of the bus. I thought it was basically impossible to get it right without assistance from the CAD tool. Am I wrong? Is this actually practically feasible with a "dumb" CAD tool like pcb? No offense, really -- I love pcb! But it's "dumb" in the sense that it doesn't really contribute to the layout, just does a pretty good job of letting you do the layout. I've never had much luck with the autorouter even for moderately complex stuff, nevermind creating balanced busses. -- Randall _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
