# Best way to connect multiple serial UART sensors to Node-Red?

**URL:** <https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980>\
**Category:** General\
**Created:** [28 October 2020 20:30 UTC](https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980 "2020-10-28T20:30:29Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![dr\_cave\_dweller](https://avatars.discourse-cdn.com/v4/letter/d/71e660/32.png) [@dr\_cave\_dweller](https://discourse.nodered.org/u/dr_cave_dweller)\
**Post date:** [28 October 2020 20:30 UTC](https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980/1 "2020-10-28T20:30:29Z")

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I have a sensor that outputs serial UART data. I connected it to a Raspberry Pi4 using a FTDI chip/cable into the USB port. Bluetooth is disabled so I am using PL011 as the primary UART (I am not using the mini UART), it is configured in Raspbian as /dev/ttyUSB0. I use the Node-Red serial communication node to read the sensor - everything is working fine, no problem.

However, I can't figure out how to add multiple UART serial sensors to Node-Red, say I want to use 2/3/4/5 of the same sensor.

The raspberry Pi1/2/3 only haa 1 PL011 UART channel (UART0), but the Raspberry Pi 4 has 5 (UART0/2/3/4/5) according to this document

> **[Teach, Learn, and Make with Raspberry Pi – Raspberry Pi](https://www.raspberrypi.org/documentation/configuration/uart.md)**
>
> The Raspberry Pi is a tiny and affordable computer that you can use to learn programming through fun, practical projects. Join the global Raspberry Pi community.

So is it possible to setup Raspbery Pi 4 / Node-Red to have 5 serial sensors via 5 separate FTDI chips/cables over a USB hub? Is this possible / the correct way to accomplish this task?

Or would I be better off trying to interface the UART sensors to a small microcontroller that aggregates the data and outputs one string of data to the Pi? Or maybe build a small UART to SPI or I2C bridge for each sensor and poll the sensors this way over a single data line?

Any tips appreciated. Thanks

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**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\
**Post date:** [28 October 2020 21:03 UTC](https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980/2 "2020-10-28T21:03:09Z")

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Somebody here may know the answer, but the question isn't anything to do with node red. If you can find how to connect multiple serial ports to the Pi then node-red will be able to access then just by specifying the appropriate /dev/... port in the serial node.

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**Author:** ![dceejay](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/dceejay/32/38_2.png) [@dceejay](https://discourse.nodered.org/u/dceejay)\
**Post date:** [28 October 2020 22:18 UTC](https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980/3 "2020-10-28T22:18:08Z")

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odd - when I use my "old" FTDI USB-Serial adapter it turns up as /dev/ttyUSB0 - and I can plug in 3 or 4 of them and get /dev/vttyUSB1 2 3 etc...

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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:** [27 December 2020 22:18 UTC](https://discourse.nodered.org/t/best-way-to-connect-multiple-serial-uart-sensors-to-node-red/34980/4 "2020-12-27T22:18:33Z")

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