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Altera_Forum's avatar
Altera_Forum
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20 years ago

Anybody know this ?

Hi, I use Nios3.1, QuartusII 4.0, and APEX 20KE.

I use ISR and DMA to design my circuit. And I have a question now.

I hope to know that how much time does the nr_installuserisr() function will take ?

I mean it is an empty call, and the content within the ISR is empty.

How much time this calling will take, or this is uncertain ??

Can anyone tell me ??

Thanks a lot. http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/smile.gif

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    20 years ago

    Are you asking how long is nr_installuserisr() or the actual ISR itself? (nr_installuserisr() just gets things setup so that an interupt will trigger your ISR). The install routine is just part of the constant setup time of your system so I&#39;m a little bit confused why you want to know (unless you have one of those systems that has to come out of reset very quickly).

    Here&#39;s the exception handler documenation: http://www.altera.com/literature/an/an284.pdf (http://www.altera.com/literature/an/an284.pdf)

    I saw some benchmarks in there for the specific software example that is included (Uart).