On Fri, 2011-04-08 at 07:44 -0400, V G wrote: > On Fri, Apr 8, 2011 at 6:23 AM, Mike Harrison wrot= e: >=20 > > A few - onboard memory will probably be the first limit you hit > > >=20 > Thanks. I'll look for memory upgrade options. The options are get a bigger FPGA, trying to tack on memory gets very messy very quickly, and much more pricey (unless you need many MBs of memory) > As above, memory may be more of an issue than gate. Also for complex desi= gns > > teh compile process > > will be quicker for a larger device as it doesn't have to try so hard t= o > > fit it. > > >=20 > Is compile time *actually* an issue? I mean, to compile a C program in C3= 2, > it takes less than a second or so. How long would it take to compile an F= PGA > program when the compiler is trying hard to fit it? How long does it take= on > average? Sorry, but that question has no answer, there is no average. The time it takes to gets bits for an FPGA depends on many things, a SMALL subset is: - the size of the FPGA - the architecture of the FPGA - the version of the compiler - the size of your design - how tightly you constrain your design - how completely you constrain your design - the speed of your computer - the speed of your FPGA For a Spartan 3E, saying you choose a 1000 part and you have it relatively full, you're probably looking at up to an hour. As a minimum you'll be looking at at least a few minutes. For bigger parts it can take a day. >=20 > > Several thousand $ each., > > For example : > > > > http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=3DXC6V= LX760-L1FFG1760I-ND > > >=20 > Whoah. Why? As in, what features/performance/whatever do you get for a $2= 0 > 000 chip? Size. The LX760 is the biggest part available right now, you can cram ALOT of stuff on that chip. As for the $20k, lets just say that few would buy this part from Digikey. TTYL TTYL --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .