ModulinoKnob: report error and not last valid _pressed if read() fails

[facchinm]

Modulino/src/Modulino.h

Lines 273 to 275 in cf5e2b2

	bool isPressed() {
	get();
	return _pressed;

[AntonioBerna]

🧠 Overview

The ModulinoKnob::get() method currently has a bug where it properly returns 0 when the I2C read operation fails, but it fails to update the internal _pressed state variable. This means that subsequent calls to isPressed() will return whatever the last successfully read button state was, rather than indicating that the state is unknown/invalid.

✅ Expected behavior

When I2C communication fails, both the position value and the button state should be invalidated.

❌ Current behavior

If I2C communication fails, the position is reset to 0, but the button state remains at its last known valid value.

🎮 Reproduction

1. Successfully read a knob with button pressed (_pressed = true)
2. Disconnect the I2C bus or cause another communication failure
3. Call get() - returns 0 as expected
4. Call isPressed() - incorrectly returns true when it should acknowledge the failure

✅ Proposed solution

Update the get() method to reset _pressed to false when read fails:

int16_t get() {
  uint8_t buf[3];
  auto res = read(buf, 3);
  if (res == false) {
    _pressed = false;  // Reset pressed state on read failure
    return 0;
  }
  _pressed = (buf[2] != 0);
  int16_t ret = buf[0] | (buf[1] << 8);
  return ret;
}

[Rocketct]

ciao i've integrated your change for the get in this PR #32 as reported on the pr itself the problem is deep on the fps, because it not returns false on read now the error are handled and your solution is consistent with the expected behavior of the i2c, thnaks for your contribution @AntonioBerna 😄