基于RS422+SRIO高速长线通信的设计与实现

Design and implementation of high-speed long line communication based on RS422+SRIO

在进行飞行试验时,为解决大容量数据在传输过程中传输距离不足且传输可靠性差的问题,提出了一种基于ZYNQ的“RS422+SRIO”的数据传输方案。设计通过RS422接口电路实现对遥测组合上行指令下发及下行状态返回;并通过SRIO接口,使用Xilinx的SRIO IP核,再经过光模块连接光缆实现远距离数据发送和接收。为了防止电磁干扰导致串口接收信号的高低电平误判,增加串口精准采样软件设计,保证串口接收信号的可靠性,并在PS接收串口回传数据时使用DMA+乒乓操作的缓存方式,解决串口回传数据易丢失的问题。经大量试验验证,该方案能够通过RS422接口实现指令精准下发和状态数据的零误码接收;以及在15 km光缆连接的条件下,SRIO接口实现444.44 MB/s的零误码可靠性传输。

During the flight test, in order to solve the problem of insufficient transmission distance and poor transmission reliability during the transmission of large-capacity data, a data transmission scheme based on ZYNQ′s "RS422+SRIO" was proposed. The design uses the RS422 interface circuit to realize the sending of the telemetry combined uplink command and the return of the downlink status;and through the SRIO interface, using the SRIO IP core of Xilinx, and then connecting the optical cable through the optical module to realize long-distance data transmission and reception. In order to prevent electromagnetic interference from causing misjudgment of the high and low levels of the signal received by the serial port, the design of the serial port precise sampling software is added to ensure the reliability of the serial port signal received. The problem of easy loss of return data. It has been verified by a large number of experiments that the solution can achieve precise command issuance and zero error reception of status data through the RS422 interface;and under the condition of 15 km optical cable connection, the SRIO interface can achieve 444.44 MB/s zero error reliable transmission.