Finally connect my openjtag usb device to my old smartarm 2200 development board using openocd. The next step is buy a x86 dev board (intel galileo) and try to use openocd with it. Then port peter-bochs to support openocd, finally i will have a hardware debug platform for os dev.

http://www.zlgmcu.com is a development board company from mainland china, very good quality. My board has worked for 7 years without any component broken.