循环缓冲机制在DSP异步数据访问中的应用  

Circular Buffer Application on Asynchronous Data Access for DSP

作　　者：杨飞然[1] 吴鸣[1] 张鹏[1] 杨军[1] 

机构地区：[1]中国科学院声学研究所通信声学实验室,北京100190

出　　处：《电声技术》2013年第1期76-78,共3页Audio Engineering

摘　　要：目前,数字信号处理器(DSP)芯片被广泛应用于声频信号处理系统中,各种数据接口日趋复杂。在这些嵌入式程序设计中,经常需要在多个中断服务程序之间进行数据交互,然而在很多系统中这些中断的时钟源并不一致。由于时钟抖动使得这些中断的相对到来时刻不是固定的,导致数据传输的不可靠性。提出通过建立循环缓冲区来协调系统中异步数据的传输。该机制通过合理地选择循环缓冲区的长度,使得数据的读操作和写操作之间具有一定的延时,从而缓解了时钟抖动导致的数据丢失或覆盖问题。实验验证了该方法的有效性和稳健性。Recently, digital signal processor （DSP） is widely used in the audio signal processing systems, where the data interfaces are becoming more sophisticated. Data exchange is often done among muhiple devices in the embedded systems, however, the clock sources are different in many applications. The latency between different interrupts may be time-varying due to the clock jitter, which results in the unreliability of data transmission. In this paper, it is proposed to use the circular buffer to address this issue. The new approach introduces delay between the writing operation and the reading operation, which alleviates the data losing and the overlapping problems. Moreover, the criteria for the choice of the length of the circu- lar buffer is discussed. Experiment results confirm the effectiveness and the robustness of the new method.

关 键 词：数字信号处理器 中断访问 循环缓冲 时钟抖动 

分 类 号：TN911.7[电子电信—通信与信息系统]