Purpose: Analog comparator input and interrupt definitions.

Namespace: atmega2560::analog_comparator.

AIN0 is PE2 and AIN1 is PE3. The ADC multiplexer can supply comparator negative input when ADC is disabled and ACME is selected.

#include <atmega2560/AnalogComparator.h>
 
namespace mcu = atmega2560;
 
static_assert(mcu::analog_comparator::positive_input_pin_value == 0x42, "ATmega2560 AnalogComparator definition");

These are hardware definitions, not runtime register access or initialization.

Source: ATmega2560 datasheet (DS40002211A).