AnalogRead Broken

Troubleshooting
1

Having some problems with a new Boron board. Firmware 1.4.0.

The ADC does not seem to work at all.

This code just produces low values from 0 when grounded to 30 when connected to source 3.3V.

Surely it cant be this hard to read ADC. Or is my adc dead? I only have the one Boron right now.

SYSTEM_MODE(MANUAL);

void setup() {
  Serial.begin();
}

void loop() {
  Serial.println(analogRead(A3));
  delay(200);
}
2

Hey @jack4566

Try something like

Serial.printf("%d\n",analogRead(A3));

Instead of your println. Remember, you can’t expose your ADC pin to anything more than 3.3V.

Also, if you have a battery hooked up you can read the battery voltage to make sure:

float voltage = analogRead(BATT) * 0.0011224;
Serial.printf("%.2f\n",voltage);
3

Thanks for the help @jaredwolff
.
I tried this code and tested all the pins. A0, A1, A2, A4 all work. A3 does not. Since its the pin i have been testing with i think it it got fried. My circuit should only feed 0-1.0v so its odd that i blew it up.

I did also try toggling the pin as a digital output. The neighboring pins work fine, 0-3.3, while pin 16 only moves 0-0.3v. I think its shorted somewhere.

Ill order a new boron and try again.

  Serial.printf("%d  ",analogRead(A0));
  Serial.printf("%d  ",analogRead(A1));
  Serial.printf("%d  ",analogRead(A2));
  Serial.printf("%d  ",analogRead(A3));
  Serial.printf("%d\n",analogRead(A4));
  delay(500);
4

Yea, it’s likely damaged, When you’re testing, there’s nothing connected, right?

5

Just my scope (10M)
Then i toggle the analog pins between reference ground and 3.3v.

6

Gotcha. Well, at least you can use the other pins. (Unless you need all of those too!)