Strange quartus 11.1sp1 behavior...

[Altera_Forum]

Every once in a while quartus changes my specified target device from a cyclone 4E to a cyclone 4GX. I never click anything else but the compile button in the GUI. I do all my text editing outside of Quartus. And I am not changing any project settings or project files outside of the GUI. This must be some kind of bug. Too bad I don't know exactly what causes it so I could reproduce it on demand and file a bug report. :( 

 The only way I notice when it happens is when quartus gets to the fitter stage and says some of my pin constraints don't make sense (since those particular pins don't exist in the GX part).  Has anyone else experienced this? I am running 11.1sp1.

[Altera_Forum]

odd. Try raising a support request with altera mysupport

[Altera_Forum]

I'm not even going to bother. The very first thing they'll ask me for is a design which will reproduce the issue. Which I don't have. So then they'll try to reproduce it themselves - which they won't be able to - then they'll essentially say sorry and close the case. A waste of time. If I figure out what causes it I will open a support case.

[Altera_Forum]

that's really odd, but i agree with it being difficult to support bugs that are hard to reproduce 

 as a work around, you could build your project using a Tcl script, etc

[Altera_Forum]

I'm really glad you brought that up actually. Does altera have a good doc on how to create a basic Tcl script? I would much rather run everything as a script. I know how to do it with the Xilinx tools, I just haven't taken the time to figure it out for the altera tools. Can you point me in the right direction to get started? As you suggest, I'll bet that using a script will completely get rid of the problem.

[Altera_Forum]

i'm sure it would solve the problem. some how, the Quartus Settings File (.qsf) is getting corrupted. using the Tcl flow generates the .qsf every time its run. the painful part is back annotating things from a sandbox .qsf to your source Tcl 

 there are examples out there, i'll take a look later

[Altera_Forum]

take a look at page 8: 

 http://www.altera.com/literature/hb/qts/qts_qii52003.pdf

[Altera_Forum]

some NEEK projects build from source: 

 http://www.alterawiki.com/wiki/neek_video_design_example