On a typical arduino board (e.g. atmega 328p) the following code will initialize I2C then disable the internal pullup resistors:
But on a T4.x, this doesn't work because using
Unless there's some precedent I'm unaware of, I think for compatibility purposes activating the pulldowns should only be possible using
C:
Wire.begin();
digitalWrite(SDA, LOW);
digitalWrite(SCL, LOW);digitalWrite(x, LOW) activates the pulldown resistors. This behaviour doesn't seem to be mentioned anywhere in the arduino documentation and makes code incompatible between platforms.Unless there's some precedent I'm unaware of, I think for compatibility purposes activating the pulldowns should only be possible using
pinMode(x, INPUT_PULLDOWN) and calling digitalWrite(x, LOW) on a pin that was previously set to INPUT mode should turn off the pullup. Additionally, the pullup/down pad fields are the only things that should be modified e.g. not the drive strength or open-drain configuration.
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