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. I made it for fun.
– Temp sensor (+/- .5 deg C)
– USB 2.0
– Windows/Linux software
– Poll up to 100 times/minute– In-circuit programming– Only 11 components– Indicator LED
The EnvStick shows up as a serial port – a COM port on Windows boxes. Here 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.
On the right are some of the initial EnvStick attempts. It took me a couple tries to get a board that worked without lots of manual “fixes”.
Here’s the schematic. Click for a larger version.
For more detail: EnvStick USB Temperature Sensor using PIC12F683