I am reading serial from a sensor, using following code: Adafruit_PM25AQI/PM25_test.ino at master · adafruit/Adafruit_PM25AQI · GitHub There's an Arduino library that I installed, and the code compiles and runs. But my serial monitor shows this: Adafruit PMSA003I Air Quality Sensor 5.0um / 0.1L air:1 Particles > 10 um / 0.1L air:0 --------------------------------------- ** > 2.5um / 0.1L air:5** Particles > 5.0um / 0.1L air:1 Particles > 10 um / 0.1L air:0 --------------------------------------- ** > 2.5um / 0.1L air:5** Particles > 5.0um / 0.1L air:1 Particles > 10 um / 0.1L air:0 --------------------------------------- =e i0K[kCanR ۛi0n5K[BL,CћZR n5BhND4Vf,ћ%ZHDO՚l ,OhD)VZ( )HD5$FU%M O7̨D)DZۛM )(OۛG l `ɛ Ê **And the rest is gibberish ** Any ideas?

@joelt42, your topic has been moved to a more suitable location on the forum. Intruductory tutorials is for tutorials that you write to help others, not for questions. Feel free to write a tutorial once you have mastered the problem :wink:

[image] joelt42: =e *i0K[k*CanR ۛi0n5K[BL,CћZR n5BhND4Vf,ћ%ZHDO՚l ,OhD)VZ( )HD5$FU%M O7̨D)DZۛM )(OۛG l `ɛ Ê **And the rest is gibberish ** I get this sort of problem with high numbers in Serial.begin(115200); A test would be to try 9600 to rule that out.

Slight errors in the serial baud rate due to CPU clock inaccuracies can lead to such gibberish. Which MCU/Arduino are you using, and what is the clock frequency?

Hi, @joelt42 Welcome to the forum. Please read the post at the start of any forum , entitled "How to use this Forum". [image] How to get the best out of this forum IDE 1.x See also FAQ - Arduino Forum for general rules on forum behaviour and etiquette. Hello, Welcome to the Arduino Forum. This guide explains how to get the best out of this forum. Please read and follow the instructions below. Being new here you might think this is having rules for the sake of rules, but that is not the case. If you don’t follow the guidelines all that happens is there is a long exchange of posts while we try to get you to tell us what we need in order to help you, which is fru… Can you post a circuit diagram? Can you please post a link to data/specs of your sensor? What model Arduino are you using? Thanks.. Tom... :smiley: :+1: :coffee: :australia:

Thanks all for the replies. I got it working. I was connectin the Uno R3 to my computer via a USB hub initially. When I went directly into the USB port on the computer it worked.

Reading Serial Problems

Other Hardware Sensors

TomGeorge July 11, 2021, 5:03am 5

Hi, @joelt42
Welcome to the forum.

Please read the post at the start of any forum , entitled "How to use this Forum".

Can you post a circuit diagram?
Can you please post a link to data/specs of your sensor?
What model Arduino are you using?

Thanks.. Tom...

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Reading Serial Problems

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