I recently made a sensor using my Arduino that essentially displays the distance between an object continuously, it outputs to the serial monitor with no issue whatsoever. I wanted to spice it up by connecting it to my Pi and playing music whenever the distance would be a certain value, and saw that…

If your raspberry pi is not headless you can use an exec node to start chrome on your Raspberry pi.

Can i still do that headless? I connect to it via remote desktop. So this exec node would basically take in the command of, say "if msg.payload = distance: 20cm, thne pop up browser with video" and work?

yes, although on Rasperry Pi you can also use OmxPlayer and youtube-dl to play videos directly to the frame buffer, see https://www.raspberrypi.org/forums/viewtopic.php?t=63632 You could also use the Exec node for that.

That's cool I think I almost get it now, just unsure of how one triggers the exec node whenever the condition is true. For example if (msg.payload = 'Distance 20cm') { --do something to trigger exec node }

[image] Kanjo: just unsure of how one triggers the exec node whenever the condition is true. If that is the only thing happening in the function node, I'd use a switch node and then connect the output to an exec node to run what you want. Also if you use this if (msg.payload = 'Distance 20c…

Here's an example with a change node (to extract the number) and a switch node. The advantage here is you can do things like greater than or less than in the switch node: [{"id":"169422d2.3157e5","type":"inject","z":"853cfa30.9644a","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"rep…

Uh I'm not sure if it's me but I just see this: [image] I'm new to the site and Node Red, so I'm unsure if that is what I'm supposed to see or not

Did you copy the flow and import it? If you put your cursor near the end of the line, a copy icon should show up or you can select the entire line and copy/paste it into your flow.

Oh shoot I did not know that, thank you so much for letting me know. Played around with both your flows and learnt a lot from the nodes. Several questions however: I intended on making the switch node pick up the output from my Arduino, but was unsure of how to actually pull out, say "Distance: 20…

Without seeing the actual data coming from the arduino it is hard to give you an answer. As for the second question, please provide the flow.

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How to trigger a web page to pop up the minute a serial output satisfies a condition?

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How to trigger a web page to pop up the minute a serial output satisfies a condition?

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