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At this stage HART bus communication has become the industry standard in the field of industrial automation instrument, but this HART MODEM which based on the USB bus interface has some problems in practical applications of the engineering,such as poor practicability, poor portability ,and high cost of purchase.Therefore, this paper puts forward a kind of research and application of HART MODEM module based on USB bus interface,its purpose is to replace the existing HART MODEM module which based on serial bus interface,at the same time solve the problems existing in the current module.In this paper the HART MODEM module based on USB bus interface uses the STC89C51RD microcontroller as the core,through the USB driver chip CH375A receiving the HART protocol frame which from PC,while the protocol frame is forwarded to the HART bus instrument in the industrial field by DS8500 HART modem chip. Through experiment and application verification,the noise immunity and communication bit error rate of the module reaches the industrial product index,and widely used in automation instrument ,such as pressure transmitter, temperature transmitter, flowmeter, actuator, and other fields.