fifo头参考资料，可用来参考写ov7670的驱动代码-the fifo head reference materials that can be used to refer to the write ov7670 drive code

OV7670开发文档,开发工具手册。包括了OV7670的时序图，寄存器的配置方式-OV7670 development documentation, development tools manual. Including the manner of the OV7670 a timing chart, the register configuration of