2021-11-27T07:00:00Z (UTC) I am following a tutorial in book "Programming with Node-RED" by Dogan Ibrahim Using TMP 36, MCP3002 , on Raspberry pi 3 B. I received the error message in the subject bar above. I have been over my wiring and confirmed connections to TMP MCP3002 and Rpi GPIO. I woul…

Hi @Loonhaunt Can you provide more specific details as to what you've done, where you see that error and any other relevant details?

I will do my best. I followed a tutorial that had a pi reading from a TMP 36 temperature sensor utilizing a MCP3002 ADC connected to GPIO 7,9,10,11. The output was set up to go to a dashboard with a gage and a chart. The TMP was obviously not getting read as the gage never showed anything other th…

I recommend watching this playlist: Node-RED Essentials . The videos are done by the developers of node-red. They're nice & short and to the point. You will understand a whole lot more in about 1 hour. A small investment for a lot of gain.

An error like that is most likely coming from a Function node. If you hover over the error message in the debug sidebar it will highlight which node logged it. If the node isnt currently visible then you should see its id in the too right corner of the debug message. Click on that should take you t…

Hello, The message comes is at this point in my flow at A/D Converter Node node-red-node-pi-mcp3008 (node) - Node-RED (I see you are a Maintainer) I am assuming at this point that there may be a problem upstream in my circuit. I noticed that my temp sensor a TMP36 was over heating, which could …

Give the mcp node a name and check that the error message shows that name above it in the debug pane.

Done. Changed Name to TempRead. This name did show up in the error message. This then indicates that either the MCP3/D3002 is not reading the TMP3002, or the 3002 is not connected to the correct GPIO pins. I don't see how the Rpi knows which GPIO it is supposed to be reading by looking at eithe…

[image] Loonhaunt: I don't see how the Rpi knows which GPIO it is supposed to be reading I don't think there is a choice with SPI is there? Not that I have ever used it.

Did you run raspi-config as described on the page you linked to? When you send the node a message what do you get out? Wire it to a config [Edit: debug] node and show us what it says. You can paste a screenshot of the debug pane here. Also please stop node red and start it again in a terminal and…

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TypeError: Cannot read property 'dnum' of undefined

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Loonhaunt 28 November 2021 23:35 11

Oh yes that is correct.

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TypeError: Cannot read property 'dnum' of undefined

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