Design And Implementation Of Interface Board For 340MHz Wireless Transceiver

340MHz band is the Ministry of Industry and Information Technology division of public safety emergency communications wireless video transmission band, the band has a strong electromagnetic wave diffraction performance, it can also reduce the burden of 3G spectrum resources. Many companies are now developing the band wireless products, and the normal operation of the wireless transceiver is an important part of product development. In order to ensure the normal operation of the wireless transceiver which must have the stable control signal transmission, so this paper designs a control interface board based on 340MHz wireless transceiver, and it has laid a solid foundation for the stable work of wireless transceiver .At present, there are many ways to realize the control interface board, such as the use of DSP, ARM or microcontroller, etc., but the cost is more expensive, or less communication interface. This thesis chooses the CPLD-based hardware platform and uses the parallel port mode for the interface board design, which is a compromise for the cost and resource utilization.This thesis starts from the overall design of the interface board and describes the whole design frame, then it has a detailed circuit design which is focused on the parallel interface circuit, CPLD minimum system, power supply circuit, D / A conversion circuit, etc. and it has hardware coding for EPP parallel interface and selection of data channel using Verilog HDL language, and it completes the PC master software design process with C # language. The improvements of the design are following mainly :(1) it uses CPLD device for signal transmission control to ensure signal stability and to avoid the design complexity of the traditional discrete components building the circuit;(2) Data channels choose from one-hot coding for achieving the state transition, to enhance the overall stability of the system;(3)it uses software design for implement I2C bus and SPI bus, reducing the use of CPLD resources and the complexity of coding, and increasing design flexibility.Finally, the design debugs the interface board and the wireless transceiver, according to the debug results show, the wireless transceiver can transmit and receive340MHz band signal correctly, and it evidences that the design of the interface board is correct furtherly.