The integration time is stored in the SYSALS__INTEGRATION_PERIOD (0x0040) in milliseconds. My idea is to use a combination of an RTC such as DS3231 and an internal timer/counter in Arduino. Here is a general idea how it would work: RTC generates a signal every 1 second, and I don't mean just 1 Hz frequency signal, but a signal when a new second starts according to real time (at 000. I need to calculate the delay of sending data from Arduino A to Arduino B. It does have a 32kHz square-wave output for a. When the future is dazzlingly-bright, this ultra-high-range luminosity sensor will help you measure it. The TSL2591 luminosity sensor is an advanced digital light sensor, ideal for use in a wide range of light situations. Visible light intensity is also know as lux.