This is extremely simple to build PIC Temperature meter that allows to measure temperature in two different locations at the same time. Never before such a useful and powerful circuit could be built with so little components and yet provide endless possibilities. This is all possible thanks to the use of PIC16F628 microcontroller and 2into16 character LCD display that act like a small computer which can be customizable thanks to upgradeable hex firmware.
Presented PIC temperature meter uses two very exciting DS18S20 digital temperature sensors that come in convenient TO92 package. Unlike regular sensors where temperature readings are passed as varying voltage, DS18S20 passes temperature information in a digital format as data. This brings many new possibilities and enables to pass temperature information over much longer distances just over a two wire cable. With this temperature can be measured in different locations at the same time and away from the main circuit board. With regular sensors which rely on the varying voltage cables must be as short as possible because longer wires introduce stray resistance that bring unreliable readings.
Once PIC microcontroller receives temperature information it converts it into both Celsius and Fahrenheit values so that they can be displayed on LCD display. PIC temperature meter is capable of measuring temperatures from -55 to 125 °C degrees Celsius (-67 to 257 °F Fahrenheit) with 0.5 °C / 1 °F accuracy. If you just need to measure the temperature in one location you may just use one DS18S20 sensor and PIC16F628 microcontroller will automatically pick it up
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