keeping signals for signaltap

[nicoh]

Hi,

I'm using Quartus prime lite edition (language VHDL).

how can I "keep" signals so they appear in the siganltap search? 

[sstrell]

If you want to preserve signals to tap as post-fit signals, you can use the "keep" and/or "preserve" synthesis attributes in your HDL code.  There is a preserve for debug feature that uses project assignments, but that's only in the Pro edition of the tool.  You can also just tap the signals pre-synthesis, basically tapping the signals directly from your RTL code.

[nicoh]

I tried the "keep" and/or "preserve" (I always look for pre-synthesis) and doesn't work.. 

[sstrell]

What exactly are you trying to tap?

[nicoh]

some internal signals in my project (flag, counter, etc) 

[ShengN_Intel · Accepted solution]

Hi,

May be can try with attribute noprune check this https://www.intel.com/content/www/us/en/programmable/quartushelp/17.0/hdl/vhdl/vhdl_file_dir_noprune.htm, adding virtual pins in the Assignment Editor or use "pre-synthesis" filter in SignalTap's node selector and tapped the signal inside a "component" rather than in the top-entity where it is generated.

Thanks,

Best regards,

Sheng

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