According to the requirement of the design, the MP3 decoding module, WiFi module, Power amplifier module, Audio channel selection module, Bluetooth audio receiver module and radio module was designed. STM32 series microcontroller is the main control chip, the music in other storage media are decoded and played through the MP3 decoder chip. By selecting a sound module like Bluetooth audio module, WiFi wireless connection with mobile or receiving music by radio module, input can be given to amplifier. In this design, data transmission by the wireless way can reduce wiring work.
Hardware Circuit Design
The circuit consists of the single chip microcomputer, audio decoding circuit, wireless communication circuit radio circuit, display circuit, etc. It can realize MP3 playing, radio, mobile phone operation and other functions.
The microcontroller is initialized, then LCD screen, audio decoding module, Bluetooth module, radio module, etc are initialized. After that display interface is designed, followed by designing the audio decoding program to decode the MP# format file. Next, we designed the WiFi wireless module program to achieve wireless communication with mobile phone. Lastly, the radio module program is designed to achieve the listening function.