图解USB总线枚举过程，最直观地介绍了USB总线的总线枚举过程。-USB bus enumeration process diagram, the most intuitive descr iption of the USB bus enumeration process of the bus.

Atmel CPUs come at internal 1Mhz clock. To use USBasp you need to use a SPI clock under 1/4 of the clock, menas under 250Khz. By default the USBasp uses 375Khz and is unuseable for new AVR CPUs. This file (must rename to usbdrv.c before compile) is f

USB DMX512 控制通信代码，C语音。-DMX512 CODE