# Serial Communication between Arduino and Node Red

**URL:** <https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296>\
**Category:** General\
**Tags:** function-node\
**Created:** [27 September 2024 07:40 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296 "2024-09-27T07:40:52Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Biotknifish](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Biotknifish](https://discourse.nodered.org/u/Biotknifish)\
**Post date:** [27 September 2024 07:40 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296/1 "2024-09-27T07:40:52Z")

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Hi. I´m working in a proyect with 3 Arduino´s Mega 2560 and I want to send some data from the controler to Node Red. I need to use the Serial In (3 different blocks) and when I ´m trying to assign the port (COM3, COM4 & COM5) I can´t. The program change automatically all ports to the same. Any help please? Thank you 😉

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [27 September 2024 07:56 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296/2 "2024-09-27T07:56:12Z")

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> [@Biotknifish](#):
>
> The program change automatically all ports to the same. Any help please?

You are updating the 1 serial config. Thats why all 3 nodes have the same setting.

Instead, add 3 individual configs and set each node to use its own config.

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<div class="post-metadata">

**Author:** ![Biotknifish](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Biotknifish](https://discourse.nodered.org/u/Biotknifish)\
**Post date:** [27 September 2024 08:42 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296/3 "2024-09-27T08:42:12Z")

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How can I add 3 individual configs? Thank you for your time

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<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [27 September 2024 08:46 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296/4 "2024-09-27T08:46:39Z")

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open 1 node, select the serial config dropdown, select "add new config", give is a recognisable name like "This is COM 3"

If you are using latest Node-RED, this is simpler - click the `[+]` button

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/c/ecb6cbfcddf3933d69584f1ea3365ac2734c16bf.png)

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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:** [11 October 2024 08:47 UTC](https://discourse.nodered.org/t/serial-communication-between-arduino-and-node-red/91296/5 "2024-10-11T08:47:31Z")

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