Validate DS18B20 CRC #14
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This solves #13 by reading the complete scratchpad and validating the CRC at the end of it. When the device is not connected, every call to
DS18B20_ReadBytewill yield0xFF, so the CRC will not match.This is then used to send the bytes
0x80,0x00as the temperature value, which equates to a value far outside of realistic temperatures (far below absolute zero). This makes it easy to determine whether a reading is correct or not.