We have for a long time wanted a temperature logger and this has resulted in this project. We choose to interface the thermometer through USB as this is todays best standard. When the thermometer is connected to the PC you operate it through my brothers program written in Realbasic.
Update: On request from Andre in Russia we have updated the pic program to enable it to use a DS18B20 thermometer chip with 0.1 C resolution. The Windows software is updated accordingly.
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When the USB thermometer is connected to the PC you can set the thermometer real time clock, read the current temperature and all the stored temperature measurement series.