# Serial port / dev / ttyUSB0

**URL:** <https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339>\
**Category:** General\
**Created:** [14 January 2020 21:12 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339 "2020-01-14T21:12:36Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![fabien](https://avatars.discourse-cdn.com/v4/letter/f/85e7bf/32.png) [@fabien](https://discourse.nodered.org/u/fabien)\
**Post date:** [14 January 2020 21:12 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/1 "2020-01-14T21:12:36Z")

</div>

serial port / dev / ttyUSB0 problem  
hello, i'm trying to wire two arduino on two ports / dev / ttyUSB0 and USB1.  
but when I change the parameters usb1 serial port to an output node, at the same time another input node at USB1 to USB0 exchange.  
Can we have two different serial ports on node red?

---

<div class="post-metadata">

**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [14 January 2020 21:30 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/2 "2020-01-14T21:30:41Z")

</div>

It depends on the hardware. Which platform are you on?

---

<div class="post-metadata">

**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [14 January 2020 21:48 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/3 "2020-01-14T21:48:23Z")

</div>

I think you have discovered a bug.

I added /dev/ttyS0 as an input node and then /dev/ttyS1 as another input node and the first node changed to /dev/ttyS1 after I opened the configuration nodes tab (which only showed /dev/ttyS1

This is one for @dceejay

---

<div class="post-metadata">

**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:** [14 January 2020 21:53 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/4 "2020-01-14T21:53:07Z")

</div>

Depends if you add a new one or just edit the existing  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/9/c/9cdb9ca5ff46704933bf60e9e643807d5630e41e.jpeg)

You need to add the second

---

<div class="post-metadata">

**Author:** ![ghayne](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/ghayne/32/39_2.png) [@ghayne](https://discourse.nodered.org/u/ghayne)\
**Post date:** [14 January 2020 21:57 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/5 "2020-01-14T21:57:33Z")

</div>

Thanks Dave, now it makes sense.

---

<div class="post-metadata">

**Author:** ![fabien](https://avatars.discourse-cdn.com/v4/letter/f/85e7bf/32.png) [@fabien](https://discourse.nodered.org/u/fabien)\
**Post date:** [30 January 2020 19:11 UTC](https://discourse.nodered.org/t/serial-port-dev-ttyusb0/20339/6 "2020-01-30T19:11:24Z")

</div>

Thank you for your reply