EnvStick USB temperature sensor
The EnvStick is cheap, homemade temperature sensor that plugs into a USB port. It provides a simple way to collect a room’s ambient temperature.The EnvStick shows up as a serial port - a COM port on Windows boxes. You can see the typical output (on a program like Hyperterminal) - it waits a specified number of seconds, spits out a temperature reading, and starts waiting again. If you press “p”, you can set the number of seconds in between each temperature reading.
   EnvStick USB temperature sensor
See more on EnvStick USB temperature sensor website
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