说明：  Keil ULINK2 USB-JTAG 适配器通过USB 端口将PC机与目标硬件（经JTAG 或 OCDS）连接起来 ，可以实现，下载程序到目标硬件上进行测试。
(Keil ULINK2 USB-JTAG adapter through the USB port to PC, with the target hardware (via JTAG or OCDS) link can be achieved, download program to the target hardware for testing.)