Forum Discussion
New ContributorSignal Tap false trigger
Super ContributorHi,
a popular reason for experiencing "false trigger" or incorrectly acquired signals is tapping signals that are asynchronous to signal tap acquisition clock. Respective signals usually generate timing failure in timing analysis.
Seeing no data before trigger event simply means that trigger condition is immediately met.
Regard
Frank
New ContributorI temporarily resolved this issue by disabling the hps debug port. Please see the image below.
Based on my experience, even with immediate triggering, all waveforms should be displayed. For example, if I set all conditions to "don't care," it triggers immediately, but the captured waveform is different from what I described.
- sstrell
At the bottom of the Signal Configuration section of Signal Tap, did you have the Trigger In feature enabled using the DAP as the source? That might partially explain this.
- xiaohao
"I usually don't care about this. It's the default setting. Are you referring to this?"
How should I select the nodes and triggers here? I don't need JTAG to debug the HPS.
Can you provide me with some relevant materials?- RichardT_altera
Hi xiaohao
If I understand correctly, after you disabled the HPS Debug Access Port (DAP), the Signal Tap tool was able to correctly capture both the pre-trigger and post-trigger waveforms?
HPS is not within my area of expertise, so I'm not aware if any specific settings are required for Signal Tap to work with HPS.
For relevant materials:
You may check out the timestamp 29:38 in the "Trigger In" section of this video:
Signal Tap Logic Analyzer: Basic Configuration & Trigger Conditions
Additional reference:
2.4.6.8. External TriggersCurrently, file attachments (other than images) are not working in the forum. May I know if you're using an example design or a customer design?
If it's an example design, perhaps you could guide me on where you got it from, and I’ll try to replicate it on my end.
