digitalRead() returning 0 on analog Pins

[mblees]

Hello there,

I have ran into an issue where I assumed that I can use analog pins as digital pins as usual on other controllers. However when using the digitalRead function on an analog pin while there is a voltage that should be concidered as high it returns 0.

controller: W5100S-EVB-Pico pins: 26, 27, 28 voltage: ~3,2V

expected return: 1 actual return: 0

I personally fixed this by manually implementing a threshold like this:

if (!(pin == 26 || pin == 27 || pin == 28))
    {
        return digitalRead(pin);
    }
    else
    {
        if (analogRead(pin) > 512)
        {
            return 1;
        }
        else
        {
            return 0;
        }
    }

[earlephilhower]

Analog pins read just fine digitally, but make sure you use pinMode(A0, INPUT) on them before digitalReading. The digital portion of the pad is identical to the other pads.

If that doesn't fix it, we need a complete small MCVE that shows the problem.

[mblees]

I tried but was unable to reproduce the issue using a simple script:

#include <Arduino.h>

#include "my_ethernet.h"

void setup()
{
  Serial.begin(115200);

  init_ethernet();
  while (!check_for_ethernet_link);
  while (!check_for_ethernet_connection);

  pinMode(27, INPUT); // analog Pin
  pinMode(13, INPUT); // digital Pin
}

void loop()
{
  Serial.print("Analog Pin: ");
  Serial.println(digitalRead(27));
  Serial.print("Digital Pin: ");
  Serial.println(digitalRead(13));
  Serial.println("");
  delay(1000);
}

It must have something to do with the way my electronics are set up or some other function I implemented is using the analog Pins. Therefore it seams to work as intended and my fix works for me .