# Adding another UART

**URL:** <https://community.particle.io/t/adding-another-uart/34527>\
**Category:** Firmware\
**Created:** [July 13, 2017, 9:53am UTC](https://community.particle.io/t/adding-another-uart/34527 "2017-07-13T09:53:43Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Nemiah](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/nemiah/32/16391_2.png) [@Nemiah](https://community.particle.io/u/Nemiah)\
**Post date:** [July 13, 2017, 9:53am UTC](https://community.particle.io/t/adding-another-uart/34527/1 "2017-07-13T09:53:43Z")

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Can something like this be done on the Photon?

> **[Creating a new Serial | Using ATSAMD21 SERCOM for more SPI, I2C and Serial ports...](https://learn.adafruit.com/using-atsamd21-sercom-to-add-more-spi-i2c-serial-ports/creating-a-new-serial)**
>
> Get more high speed serial commports without bitbanging

Or does anyone know of an SPI/I2C to UART bridge?

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**Author:** ![ScruffR](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/scruffr/32/6952_2.png) [@ScruffR](https://community.particle.io/u/ScruffR)\
**Post date:** [July 13, 2017, 10:23am UTC](https://community.particle.io/t/adding-another-uart/34527/2 "2017-07-13T10:23:55Z")

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You mean like this?  
[https://build.particle.io/libs/ParticleSoftSerial/0.0.5](https://build.particle.io/libs/ParticleSoftSerial/0.0.5)

This is not really a SPI/I2C-UART bridge but sounds similar to the intent of the link.

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<div class="post-metadata">

**Author:** ![Nemiah](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/nemiah/32/16391_2.png) [@Nemiah](https://community.particle.io/u/Nemiah)\
**Post date:** [July 13, 2017, 10:50am UTC](https://community.particle.io/t/adding-another-uart/34527/3 "2017-07-13T10:50:57Z")

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Cheers, that would do it, from other searches I’d done ppl were saying that you couldn’t do software serial on the photon because of the precise timing and interrupts would interfere with the background processes.

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<div class="post-metadata">

**Author:** ![ScruffR](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/scruffr/32/6952_2.png) [@ScruffR](https://community.particle.io/u/ScruffR)\
**Post date:** [July 13, 2017, 2:59pm UTC](https://community.particle.io/t/adding-another-uart/34527/4 "2017-07-13T14:59:46Z")

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Hence I wrote this library to fill the gap but this is limited to baudrates bellow 36000 for the reason of the interrupt latency impact.