SOF Files content are Different after each time of Compilation!!!! Is It Normal??

knowfish,

Did you remove this thread? I received an email that you had updated it, but when I clicked on the link it says it was invalid. I thought the poster name on that one was vitlachbach? (I have an issue where I see posts I can answer, but often click on them and the link is invalid, and so trying to track down if it's a technical issue or the original poster taking it down, changing it, etc.)

FYI, I can't see the .jpg files(I downloaded them, but the screenshots are too coarse grained). I assume it's a diff showing different files.

1) There is no random number generator or anything like that in Quartus, so given the same inputs, as previously discussed, will produce the same outputs. Is there a QSYS system in your project, as sometimes those have an ID component, which puts a timestamp in it.

2) Debugging what's causing this can be a pain. What I recommend is starting with the .map.rpt and diffing them. I would actually start with the messages at the bottom. It may take a little massaging, i.e. if the projects are in different locations then the reports will all show different paths, so you have to do a search and replace, but you can get there.

3) Why are you worried about this? The number one reason of concern is the case I mentioned earlier, whereby there is an image in the field and the entire project wasn't saved. There might be a problem and they want to go back to that exact fit and run Timequest on it, or do a post-fit SignalTap, to try and debug the issue. Again, in most circumstances it's easier to just zip up everything including the /db. If you're finding that you get different results and some of them work and some of them don't, then I would worry much more about why the non-working ones fail. Different results should just be like a different seed, e.g. a randomly different fit that is still trying to meet all of your requirements. If the design is fully constrained, then both designs should work and you shouldn't be able to tell the difference in hardware(only doing something like comparing .sofs shows a difference). In fact, I'm not sure why you're recompiling to try and get the same results. I generally keep recent results around if I need to go back and look at them. I'm not saying you don't have a good reason, and the fitter is designed to give identical results so not doing that is wrong, but I'm just checking if something else is going on.