久一网络科技

学习arm的过程中需要用到jtag，只能用usb-jtag了，而且mini2440的板子上面还是10pin的jtag，我后来发现jtag原来只用了一部分脚，找到对应的接上就好了！

下面是我从网上收集的一些资料：

http://www.hs-augsburg.de/~hhoegl/proj/usbjtag/usbjtag.html



One very useful feature of the FTDIChip FT2232C devices is that it can drive a fast synchronous serial interface like SPI or JTAG. To do that, channel one of the two-channel FT2232C has to be switched to "MPSSE" mode. The maximum clock frequency to achieve is about 6 MHz.

The other channel of the FT2232C is available for arbitrary other tasks. A typical usage is to establish a UART connection to a microprocessor target while channel one at the same time serves a JTAG connection.

Note that all the JTAG interfaces built with the FT2232C lack the adaptive clocking feature, i.e. the RTCK (return clock) JTAG signal offered by some ARM controllers, e.g. the Oki 67Q4xxx, is not supported.

Please see also my OpenOCD page: http://www.fh-augsburg.de/~hhoegl/proj/openocd/index.html