Unihedron SQM-LU, Руководство оператора

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3 Theory of operation
3.1 Light measurement
The SQM-LU measures the darkness of the night sky to provide readings of magnitudes per square arc second through a
USB connection, and is capable of internally recording readings.
A light sensor (TSL237) provides the micro-controller with a light level, and readings from the temperature sensor are
used to compensate the light sensor readings through the range of operating temperatures.
3.2 Communication to the PC
Commands sent from a PC through the USB cable to the USB interface are relayed to the micro-controller.
The micro-controller responds to commands by sending data strings to the USB interface which are then relayed to the
PC.
Readings are gathered asynchronously by the micro-controller. Requests from the PC are buffered and dealt with as
time permits.
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