32位ARM嵌入式系統(tǒng)擴展USB接口設(shè)計

基于 ARM 處理器的32 位嵌入系統(tǒng)具有極高速和大容量的數(shù)據(jù)處理能力，如何設(shè)計ARM 與主機設(shè)備或系統(tǒng)的通信接口、提升數(shù)據(jù)通信能力，成為嵌入式系統(tǒng)設(shè)計的一大問題。文章給出了一種USB 接口方案，對比RS-232 串行口，大大提高了嵌入式系統(tǒng)的數(shù)據(jù)吞吐能力，與以太網(wǎng)接口相比有即插即用特性、有塊和同步等多種數(shù)據(jù)傳輸模式，更適合音視頻碼流傳送。文章具體闡述了方案的硬件、軟件設(shè)計，并應用于音頻PCM 碼流傳送，實驗結(jié)果顯示音效流暢，方案有較高參考價值。
關(guān)鍵詞：ARM ；嵌入式系統(tǒng)；USB；音頻PCM 碼流；
Abstract：The processing speed and capability of 32bit embeded system based on ARM
procesor is very high and powerful, how to design the communication interface between ARM processor and host or other system, and how to enhance the capacity of communication,becomes a question of embeded system design. This article brings out a design of USB interface for ARM embeded system, compared with the RS-232 serial port, USB port increases the data thruput of ARM embeded system greatly, compared with the ethernet port, USB port has PnP characteristic , and has bulk transfers , isochronous transfers and other data flow types, it is more suitable for audio and vedio data flow transferring. This article discuss the hardware and software implementation detailly, and applies USB port to audio PCM stream transferring, the result show that the voice is very mellifluent, so this design is worthful to refer.
Key words：ARM, Embeded System, USB, Audio PCM stream.