摘要
RS-232接口是目前广泛应用的一种串行通讯接口,但它的传输速率较低,异步传输情况下,波特率为20kbps。在许多工程项目中,RS-232接口已无法满足需求。由Altera公司的Cyclone Ⅱ系列的FPGA与EZ-USB FX2构成的USB 2.0数据通信系统,USB数据经过FX2内部端点FIFO在主机和FPGA之间传输,FX2的CPU不参与数据传输,而USB 2.0支持的最高传输速度可达到480 Mbps,基本能够满足日益复杂的高级外设与PC机之间的高性能连接需求。软件部分由固件程序、驱动程序和应用程序3部分组成,其中应用程序由VC++6.0开发工具开发,并采用IOCOMP控件实现软件中实时曲线的绘制。经反复多次实验表明该数据通信系统运行稳定可靠,不存在采用USB-RS232数据线时所出现的掉线现象。
RS-232 interface is widely used as a serial communication interface currently,but its transmission rate is low. The baud rate is 20 kbps in case of asynchronous transmission. In many engineering projects, RS-232 interface has been unable to meet the demand. USB 2.0 supports a maximum transmission speed of up to 480 Mbps,which is essential to meet the high-performance connection needs between the increasingly complex high- level peripherals and PC. A data communication system based on USB bus is designed,which is primarily consisted of Altera＇s Cyclone II serials＇ FPGA and EZ-USB FX2. In this system, USB datas are transfered between the host and FPGA by the FX2＇s interenal endpoint FIFO, and FX2＇s CPU isn＇t involved in data transmission. Software department was consisted of firmware, drivers and applications. Aplication is designed by VC＋＋ 6.0 with IOCOMP finishing the real-time curve. The data communication system is proved to be stable and reliable by repeated lots of experiments, no dropped phenomenon exist.
出处
《桂林电子科技大学学报》
2010年第3期206-211,共6页
Journal of Guilin University of Electronic Technology
基金
广西教育厅科研基金资助项目(2008LX138)
