[SignalTap-II] Signal colors Legend

Attached please find the snapshot - you could see there Black and Blue signals... Why are the colors different? There were the Red colored signals, but I did not prepared a snapshot with them...

How should I understand a color legend of the signals in the SignalTap-II?

Thank you

Hello,

From experience, I have learnt that if your signal is getting RED, you are not going to have data captured for that signal. In this case, you are also not going to have any Trigger condition on those red signals.

I do not have any document reference and also I do not have idea about Blue signal.

Thanks,

Bhaumik

Black are Pre-Synthesis netlist nodes.

Blue are Post-Fitting netlist nodes.

Red are nodes not found in the compiled design.

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Black are Pre-Synthesis netlist nodes.

Blue are Post-Fitting netlist nodes.

Red are nodes not found in the compiled design.

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Great sharing. Thanks.

Hello,

I tried to submit a service request on the site, but I kept getting an error (attached)

I kept trying back, and I keep seeing the error. My issue is as shown in the pictures attached. The pictures are snapshots from Signal Tap.

I understand that the red nodes are not found in the compiled design, but why?

On some of the red signals, I see a signal that makes sense and looks correct (see the attached picture). So, it appears it should be a "blue" signal..

On some other red signals, it just a static '1' or '0'. In some other simulations, however, I have been able to see these static red nodes dynamically changing, and the signals are correct. This behavior seems to come and go, and I would like to understand why. I need to be able to view all of these signals in Signal Tap.

I see that this issue was never really addressed. That is, only a simple explanation was offered for what the colors meant

I look forward to talking with someone from Altera about this issue and getting to the bottom of it.

Can someone help me create a service request for this issue?

The image got resized so I can't tell what it says.

The reason why sometimes you end up with red nets in Signaltap is due to Quartus optimizations. The most common occurrence is a net that doesn't feed logic, Quartus will optimize those away. To avoid capturing nets that get optimized away when you are selecting signals to look at, make sure you use "Signaltap II: pre-synthesis" filter when locating the nets to capture. That should ensure the net is preserved and if it doesn't you can also use RTL attributes like "keep" to force Quartus to not optimize the net away.

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Hello,

From experience, I have learnt that if your signal is getting RED, you are not going to have data captured for that signal. In this case, you are also not going to have any Trigger condition on those red signals.

I do not have any document reference and also I do not have idea about Blue signal.

Thanks,

Bhaumik

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Hi Bhaunikbhai :p ,

I have found one reference training videos from Intel Altera and its link is given below:

"https://www.altera.com/customertraining/OLT/SignalTap_Intro_p1/presentation_html5.html" (go to chapter 5.7)