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HART Communication protocol

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The HART (Highway Addressable Remote Transducer) protocol is a communication protocol widely used in industrial process control and automation. It was developed in the mid-1980s by Rosemount Inc. to provide an additional digital communication channel for smart field instruments such as pressure, temperature, level, and flow transmitters. The HART protocol is a hybrid communication protocol that can transmit both analog and digital signals over a single wire pair. This allows the existing analog signal to be used for control and monitoring purposes while adding digital communication capabilities. The HART protocol operates at a low frequency of 1200 Hz and uses frequency shift keying (FSK) modulation to transmit digital signals. This method of modulation ensures that the digital signals do not interfere with the analog signal. One of the main advantages of the HART protocol is its backwards compatibility. It can communicate with existing 4-20 mA analog instruments and can be easily inte