# Arduino Multiple Sensors (Photoresistor DHT11) to Dashboard display HELP

**URL:** <https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759>\
**Category:** General\
**Tags:** node-red-dashboard, function-node\
**Created:** [12 March 2022 16:13 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759 "2022-03-12T16:13:23Z")\
**Posts on this page:** 11\
**Page:** 1

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**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 16:13 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/1 "2022-03-12T16:13:24Z")

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I need serious help cause my Professor refuses to help me or answer my emails. I am to create a multiple sensor arduino system that takes data from 3 DHT11 sensors and 3 Photoresistors. I then have to print all the values in a dashboard UI on Node red. What I am doing makes sense but does not work. Here is my workings:  
From my arduino code I get these values in my serial monitor:  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/2/3/2320c28a6a4666d0bb5a0fb6f765c64dbc5eb5c6.png)

Here is my Node red flow:

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/b/3b9fa0ea5af2b6ce01b6f82cad67f337d224fe6c.png)

and whats inside my function node:

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/6/8/689c3671971304e1295fd987eaf9c834a112ea6e.png)

After all this once i deploy, to my knowledge and research on all these nodes i should get the output on dashboard UI but all i get is....

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/5/d57a74a875a368c5137c7f639395d03a958357fe.png)

If there is anyone with an idea on how i can complete this cause ive been at this same problem for a week now and ive tried multiple things like the arduino library but nothing gives me output. Please and thank you.

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<div class="post-metadata">

**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 16:25 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/2 "2022-03-12T16:25:48Z")

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It may also be worth adding that the debug menu has no output either

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**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [12 March 2022 16:27 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/3 "2022-03-12T16:27:51Z")

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Do you actually get data from the Arduino?

What do all those debug nodes show?

If you use a dashboard gauge without changing any of the default values, and pass an msg.payload which is a number not a string, the gauge should reflect the value.

Edit - put a debug node at the output from Arduino Com3

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<div class="post-metadata">

**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 16:33 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/4 "2022-03-12T16:33:19Z")

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After deploying you can see i get nothing. is this an issue with my Serial Input?

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/a/9ad63d685eacc277becfc6c0515533c780df524e.png)

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**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [12 March 2022 17:25 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/5 "2022-03-12T17:25:44Z")

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Well yes it is.

Why don't you explain how the Arduino obtains data and interacts with your Node-red machine?  
I don't mean post the code here, explain it.  
Explaining a problem can help you see where it might be going wrong

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<div class="post-metadata">

**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 17:56 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/6 "2022-03-12T17:56:06Z")

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well i declared my pins (6 of them). then i set up my arduino on 9600 baum. then in a loop i get each variable (temp, humidity, and Light intensity) with the DHT11 library and calling the arduino anaolog pins and then print them all as serial with a comma in between. As shown in original post in the serial monitor it works fine. The node red just isnt printing them.

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**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [12 March 2022 18:16 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/7 "2022-03-12T18:16:44Z")

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What device (PC, Mac, Linux...) is your Arduino IDE running on?  
What device is Node-Red running on? If it's Windows, does Devices & Printers show the COM port?  
Can Arduino IDE and Node-red both access the com port at the same time?  
Are the Serial In node settings the same as the Arduino IDE port settings?

"node-red just isn't printing them" suggests that you are blaming node-red without (yet) adequate evidence. It's much more likely to be a problem with the interface between devices and applications.  
Try and look at it as "there is no proof that the data gets to node-red".

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<div class="post-metadata">

**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 18:36 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/8 "2022-03-12T18:36:48Z")

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I am on PC windows, Arduino IDE and Node red are connected to the same COM3. Arduino IDE and Node-red cannot be connected at the same time so i have to disconnect node red to connect the arduino and upload the code I have made. then i have to run node red which it then connects and unless im told otherwise from what i know and what i researched the serial IN is set the way it should be set.

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<div class="post-metadata">

**Author:** ![MercerMayhem](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@MercerMayhem](https://discourse.nodered.org/u/MercerMayhem)\
**Post date:** [12 March 2022 18:41 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/9 "2022-03-12T18:41:21Z")

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OK so i finally get output:

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/6/d6ed9fee66a64809924a3197557b5323fa28a80a.png)

however this took a long time for my computer to process and it should be constantly changing. For example if I change the light in a room it should change the output almost immediately.

The IDE loops with a delay of 2 seconds. should i increase it? is there anyway to make this changing faster or even at all. I have yet to see it replace the old data with new data.

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<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [12 March 2022 19:00 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/10 "2022-03-12T19:00:25Z")

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> [@MercerMayhem](#):
>
> unless im told otherwise from what i know and what i researched the serial IN is set the way it should be set.

> [@MercerMayhem](#):
>
> however this took a long time for my computer to process and it should be constantly changing.

Maybe the Serial in node help is relevant then?

```auto
The serial data reception can either

    wait for a "split" character (default \n). Also accepts escaped shortcut (e.g. \n) or hex notation (0x0d).
    wait for a timeout in milliseconds from the first character received.
    wait for a silence time in milliseconds after the last character received.
    wait to fill a fixed sized buffer.

```

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [11 May 2022 19:00 UTC](https://discourse.nodered.org/t/arduino-multiple-sensors-photoresistor-dht11-to-dashboard-display-help/59759/11 "2022-05-11T19:00:38Z")

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