基于FPGA的16位宽加载电路的8位宽加载方法

Research of Method of FPGA 8 bit Configuration Based on 16 bit Configuration Hardware

SRAM型FPGA具有掉电易失性,因此上电后需要从外部存储单元加载配置文件才能实现相应功能。分析了FPGA的配置过程和配置文件(bitstream文件)的结构,同时针对其并行加载电路,提出了一种方法,在不改变16位宽加载电路硬件的情况下,通过对文件进行修改并写入配置Flash中,最终实现让FPGA以8位宽方式完成加载。该方法的优点是既可以在高位配置引脚出现故障时降低硬件的维修成本,也可以增加研发过程中FPGA配置方式的灵活性。对该方法进行了板级测试,板级测试结果显示该方法切实可行。

SRAM-based FPGA is of volatility,which results that it needs to load configuration data from external ROM before running with some function after power up.The paper analyses the configuration procedure and construction of configuration file(bitstream file)of FPGA.Meanwhile,for parallel configuration hardware,by modifying the bitstream file and writing it into NOR Flash,the paper provides a method which makes FPGA to configure with 8 bit data,instead of changing 16 bit configuration hardware.When MSB of configuration pin failed,this method can be applied to cut the maintenance cost.It can provide more flexibility.In the end,the paper makes a test on PCB board,and the result proves that the method is available.