实时图像采集系统的DMA通道设计

Design of DMA Channel for Real-time Image Collecting System

将数字图像数据实时传送到DSP系统中进行处理,可采用多种方法完成;为了保证数字图像数据采集和处理的实时性,提出一种利用FPGA和一定容量的SRAM的DMA实现方法,通过以状态机为核心的逻辑控制实现一种大容量的组合式的FIFO作为DMA与外部数据传输的通道,整个通道通过DSP的EMIF接口实现与DMA控制器无缝接口,提高了DSP与外部数据交换的速度,适用于DSP和FPGA为主要组成的视频实时图像处理系统,数据传输率可达35M×32bit/s,实现了实时传输整幅视频图像数据的目的,使得数字信号处理器及时处理图像数据不产生延迟,提高了系统的数据处理能力和响应能力。

To transfer acquisition image data into DSPs （digital signal processors） on-chip RAM in time, it has many ways to do it. A channel composed of FPGA and specific capacity SRAM is presented, which acts as data transmission by way of DMA for digital image process system based on DSPs and FPGA . The whole channel under control of state machine stores in FPGA . The channel realizes the glueless interface between external data and EMIF of DSPs , and enhances exchange speed of DSPs and external data, rate of data transmission up to 35MX 32bit/s. So can transmit whole frame video image data in real-time and process image data in no delay, improves the ability of the data processing and system responding.