upgrade to Atmel SAM 3.50 (from 3.4.2) changed M0 (A0) output voltage - Githubissues

platformio / platform-atmelsam

Atmel SAM: development platform for PlatformIO

https://registry.platformio.org/platforms/platformio/atmelsam

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upgrade to Atmel SAM 3.50 (from 3.4.2) changed M0 (A0) output voltage #48

Open lfg6000 opened 5 years ago

lfg6000 commented 5 years ago

I upgraded from 3.4.2 to 3.5.0 and i noticed this:

hw: adafruit itsybitsy M0 (samd21)

with 3.4.2

A0 output went from 0 to 3.3v using 0 to 255
no build warning

with 3.5.0

A0 output went from 0 to 3.3v using 0 to 1024
the following build warning started showing up: ".platformio\packages\framework-arduinosam\cores\adafruit\wiring_analog.c:35:12: warning: '_dacResolution' defined but not used [-Wunused-variable] static int _dacResolution = 10;"

questions

was this intentional?

observations

arduino docs say "analogWriteResolution() sets the resolution of the analogWrite() function. It defaults to 8 bits (values between 0-255) for backward compatibility with AVR based boards."
it was a bit confusing at first
change not noted in changelog
going to trip up newbies

thanks

visual code with platformio is awesome, thank you.

ivankravets commented 5 years ago

Do you experience the same issue with Arduino IDE?