Measuring battery

[mrc-core]

Hi. I'm having some troubles when i try to read the voltage off my arduino batterys,

The problem it's not the code, my problem is the wire connection... Do i connect the battery (+) to A0 pin only or do i have the connect the battery (+) to the A0 pin and the VCC pin on the arduino pro mini ???

If i connect the arduino over USB to see the serial monitor i can see the voltage on 4.8V to 5V.
But when i try to connect to my battery the i get dead antenna.

[carleki]

Hello @mrc-core

You can use the Vcc.h library, and mesure the voltage without any wire ;)

https://github.com/Yveaux/Arduino_Vcc

[meanmrgreen]

@carmelo42

How does this work when using a booster?

[sundberg84]

@meanmrgreen - No, since the booster will output a steady voltage and thats what read in that library. If you have a booster I always use resistors and connect it to A0 (https://www.mysensors.org/build/battery). Another way is to lower BOD by burning new fuses and bootloader but this is more advanced.

[meanmrgreen]

@sundberg84
Will look into that, i have a UNO lying around aswell so prehaps ill experiment with the bootloader burning eventually.