UtilitechAS.amsreader-firmware/src/Uptime.cpp

#include "Uptime.h"

uint32_t _uptime_last_value = 0;
uint32_t _uptime_rollovers = 0;

uint64_t millis64() {
    uint32_t new_low32 = millis();
    if (new_low32 < _uptime_last_value) _uptime_rollovers++;
    _uptime_last_value = new_low32;
    return (uint64_t) _uptime_rollovers << 32 | _uptime_last_value;
}