About STP Stability

[Altera_Forum]

Hi! My question is about the stability of Signal Tap II, it seems to be strange. When i add signals to or subtract signals from my STP file, the whole program does not work at all! It's not every time, but indeed happens quite often. What's most typical is all the signals in STP will become zeros.  

I used maximum fan-out constraint, but it only worked sometime. What's wrong with this? Thanks!

[Altera_Forum]

Nobody replied? Anybody met this problem?

[Altera_Forum]

--- Quote Start ---  Nobody replied? Anybody met this problem?  --- Quote End ---    Hi,  which Quartus version do you use ? Which kind of nodes did you use ( e.g. post-fit ) ?  Kind regards  GPK

[Altera_Forum]

I'm using Quartus 9.1, and using pre-synthesis nodes. 

what's different between pre-synthesis and post-fit nodes? I have thought post-fit nodes don't work most of the time.

[Altera_Forum]

--- Quote Start ---  I'm using Quartus 9.1, and using pre-synthesis nodes. what's different between pre-synthesis and post-fit nodes? I have thought post-fit nodes don't work most of the time.  --- Quote End ---    Hi,  post-fit nodes are nodes which are left after synthesis and place&route. The problem with this nodes is that they changed during a new compilation run ( e.g. different name) and therefore no longer available. That is the reason why you will asked to lock down your design when you choose this kind of nodes.  Can please explain your problem more detailed ? E.g. what exactly do you change when it is not working ....  Kind regards  GPK

[Altera_Forum]

Hi, Happy new year 2011 (before 2012 :-) ) 

 When you add or remove signals in STP, you have to recompile the project. Normally, you can't connect to an in situ STP if it doesn't match your STP file.  Perhaps, have a look at timing constraints. STP uses a jtag clock and there will be a cross clock .... Do your design meet timing requirements ?    --- Quote Start ---   Can please explain your problem more detailed ? E.g. what exactly do you change when it is not working ....  --- Quote End ---  

[Altera_Forum]

--- Quote Start ---  Hi,  post-fit nodes are nodes which are left after synthesis and place&route. The problem with this nodes is that they changed during a new compilation run ( e.g. different name) and therefore no longer available. That is the reason why you will asked to lock down your design when you choose this kind of nodes.  Can please explain your problem more detailed ? E.g. what exactly do you change when it is not working ....  Kind regards  GPK  --- Quote End ---    Thanks for your reply!  while, i only added or subtracted some less important signals that i didn't care about, e.g. some intermediate flag signals or counter signals or calculation results, then sometimes it will not work.   Maybe it is like what you said, the signals don't exist any longer. I will try it. But can only changing signals in STP make great changes in place&route results when re-compiled?

[Altera_Forum]

Hello! Happy new year! 

   --- Quote Start ---  Hi, Happy new year 2011 (before 2012 :-) )  When you add or remove signals in STP, you have to recompile the project. Normally, you can't connect to an in situ STP if it doesn't match your STP file.  Perhaps, have a look at timing constraints. STP uses a jtag clock and there will be a cross clock .... Do your design meet timing requirements ?  --- Quote End ---    I have recompiled my project, and all the timing requirement was met. But as what i said, i used "maximum fan-out" constraint, and it will solve the problem sometime, but not every time. And I'm sure that every time all the timing requirement was met.