# Problem with SRF Node in Node-Red

**URL:** <https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944>\
**Category:** General\
**Tags:** gpio\
**Created:** [27 January 2025 21:17 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944 "2025-01-27T21:17:35Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![ItalianSquirel](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/italiansquirel/32/98383_2.png) [@ItalianSquirel](https://discourse.nodered.org/u/ItalianSquirel)\
**Post date:** [27 January 2025 21:17 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/1 "2025-01-27T21:17:35Z")

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![Error GPIO_2](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/4/34542ea43eed0903b0008d39cc855d203128cbfc.jpeg)

I work as a researcher for the Alaska Center for Energy and Power (ACEP). I work very closely with a non-profit organization called Upward Bound and a big part of that non-profit work is getting students into Programming, we start with NodeRed on Raspberry Pis.

Currently, we have a custom image based on Bookworm and some of our curriculum started breaking.

On [this forum thread](https://discourse.nodered.org/t/node-red-rpi-gpio-status-not-available/88158/22), I saw that this forum was helping the user "vani" with their efforts to do the same as I am trying to do right now (using the RPiSRF node on Bookworm). The last post on the thread was someone saying, "I've managed to bodge my Pi5 running Bookworm to get it to work". I was wondering if anyone knew of a way to get this to work without having to go back to Bullseye.

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [27 January 2025 22:44 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/2 "2025-01-27T22:44:06Z")

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I just layed out a circuit using this:

> **[How to setup a Distance Sensor on the Raspberry Pi](https://pimylifeup.com/raspberry-pi-distance-sensor/)**
>
> Learn how to use the HC-SR04 sensor with Pi.

using this circuit:

 ![Screenshot 2025-01-27 at 5.40.28 PM](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/e/de5b841e198eb3b0f8bac66bef748a75c2aa9b18.png)

and usedused Pins 7 and 11 and as you can see, it is running fine.

 ![Screenshot 2025-01-27 at 5.41.45 PM](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/3/73bd1896a3a5349aa62057aaf4dc503ef73e12bd.png)

This is on a RPI-4 running Bookworm.

What are your settings in the rip-srf node?

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**Author:** ![ItalianSquirel](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/italiansquirel/32/98383_2.png) [@ItalianSquirel](https://discourse.nodered.org/u/ItalianSquirel)\
**Post date:** [27 January 2025 23:38 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/3 "2025-01-27T23:38:07Z")

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Thanks for the quick reply! I just tried that circuit and no cigar!

This is what my node looks like:

 ![Screenshot 2025-01-27 at 2.33.41 PM](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/1/1/118d2467659748a16dad51f6452a7f2df6b0e306.png)

and this is the wiring, wired just as in the schematic:

 ![IMG_2769](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/5/e5e9de7ba4677dc8a552cd501a7184af1a226b44.jpeg)

Any other thoughts?

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**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [28 January 2025 10:53 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/4 "2025-01-28T10:53:13Z")

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It looks like you have a resistor plugged in the wrong spot

 ![Screenshot 2025-01-28 at 5.44.01 AM](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/3/c339ec0f93d6174847126b055a06d1795da978ea.jpeg)

I would suggest using a separate color wire for each connection. Having two red wires makes it confusing to trace the connections.

If that fixes the issue, it would be a good training lesson to have your students try to figure out the problem. Debugging issues is something that will benefit them in the future.

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**Author:** ![dynamicdave](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dynamicdave/32/96_2.png) [@dynamicdave](https://discourse.nodered.org/u/dynamicdave)\
**Post date:** [28 January 2025 11:17 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/5 "2025-01-28T11:17:55Z")

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I agree with @zenofmud, looks like the resistor from your 'echo' pin doesn't go to the correct point on the breadboard.  
As a suggestion, I would keep the wire-colors the same for the supply.  
i.e. Black wires for GND and Red wires for Vcc

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**Author:** ![Sean-McG](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/sean-mcg/32/54677_2.png) [@Sean-McG](https://discourse.nodered.org/u/Sean-McG)\
**Post date:** [28 January 2025 23:57 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/6 "2025-01-28T23:57:51Z")

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I agree that the resistor is in the wrong place, but just for the record the two reds are actually red and orange 😉

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [29 April 2025 03:16 UTC](https://discourse.nodered.org/t/problem-with-srf-node-in-node-red/94944/8 "2025-04-29T03:16:36Z")

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