/products/raspberry-pi/b/blog/posts/handle-raspberry-pico-pio-interrupts-in-cThere are decent examples available on how to handle PIO interrupts in C. But not so much on dealing with relative IRQs. With a normal IRQ, PIO fires an interrupt with a fixed number. The number that you give it. A relative IRQ - ...en-USTelligent Community 12https://community.element14.com/products/raspberry-pi/b/blog/posts/handle-raspberry-pico-pio-interrupts-in-cTue, 15 Apr 2025 19:21:43 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:355e4add-2319-4440-8bfd-348ee862c775DAB0<p>Nice post Jan.</p><img src="https://community.element14.com/aggbug?PostID=28831&AppID=86&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/products/raspberry-pi/b/blog/posts/handle-raspberry-pico-pio-interrupts-in-cTue, 15 Apr 2025 18:45:40 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:355e4add-2319-4440-8bfd-348ee862c775Jan Cumps0<p>For the C++ inclined crowd:&nbsp;&nbsp;[mention:301aa380c4e84007a488aadeebc7fbd4:f7d226abd59f475c9d224a79e3f0ec07:label=Handle%20Raspberry%20Pico%20PIO%20%26quot%3Brelative%20interrupts%26quot%3B%20in%20C%2B%2B]&nbsp;</p><img src="https://community.element14.com/aggbug?PostID=28831&AppID=86&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/products/raspberry-pi/b/blog/posts/handle-raspberry-pico-pio-interrupts-in-cMon, 14 Apr 2025 12:02:19 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:355e4add-2319-4440-8bfd-348ee862c775BigG0<p>Wow! I would never have figured this out from the SDK documentation. Thanks for sharing. This has really helped me.</p><img src="https://community.element14.com/aggbug?PostID=28831&AppID=86&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/products/raspberry-pi/b/blog/posts/handle-raspberry-pico-pio-interrupts-in-cSun, 13 Apr 2025 19:43:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:355e4add-2319-4440-8bfd-348ee862c775Jan Cumps0<p>If you use this on a Pico 2, you<span>&nbsp;</span>should be able to<span>&nbsp;</span>choose PIO interrupts 4 .. 7 too.</p> <p>I don&#39;t have one, so it&#39;s untested. I tried to imagine what the impact is on the code base, and adapted it.</p> <p>available on GitHub, but I didn&#39;t adapt the blog. Impacted code:</p> <p>[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:1f8a575a-b483-4cf4-b602-fea4939f0b71:type=c_cpp&text=inline%20uint%20relative_interrupt%28const%20uint32_t%20ir%2C%20const%20uint%20sm%29%20%7B%0D%0A%20%20%20%20%2F%2F%20TODO%20validate%20for%20Pico%202%20interrupts%204%20..%207%0D%0A%20%20%20%20uint32_t%20retval%20%3D%20ir%20%26%200x03%3B%20%2F%2F%20last%202%20bits%0D%0A%20%20%20%20retval%20%2B%3D%20sm%3B%20%2F%2F%20add%20relative%20value%20%28is%20sm%29%0D%0A%20%20%20%20retval%20%3D%20retval%20%25%204%3B%20%2F%2F%20mod%204%0D%0A%20%20%20%20%2F%2F%20TODO%20most%20likely%20I%20have%20to%20restore%20bits%2031..2%20here%20to%20work%20with%20Pico%202%0D%0A%20%20%20%20%2F%2F%20but%20I%20don%27t%20have%20one%20to%20test%20it%0D%0A%20%20%20%20retval%20%7C%3D%20ir%20%26%200xfffffffc%3B%0D%0A%20%20%20%20return%20retval%3B%0D%0A%7D]</p> <img src="https://community.element14.com/aggbug?PostID=28831&AppID=86&AppType=Weblog&ContentType=0" width="1" height="1">