CH347是一款高速USB总线转接芯片，通过USB总线提供UART、I2C、SPI、JTAG等接口。
本章节介绍如何在OpenOCD中添加CH347-JTAG接口，通过OpenOCD可操作CH347进行JTAG调试或下载应用。
OpenOCD增加CH347配置文件，用于型号识别，操作方式：
adapter driver ch347
ch347 vid_pid 0x1a86 0x55dd
adapter speed 10000
此文件为设备驱动文件，提供JTAG core操作CH347的API接口函数
修改配置文件 configure.ac 1、OpenOCD根目录下configure.ac文件，添加CH347接口驱动支持：
a. m4_define([USB1_ADAPTERS]中添加CH347接口
m4_define([USB1_ADAPTERS],
[[[ftdi], [MPSSE mode of FTDI based devices], [FTDI]],
[[ch347], [Mode 3 of the CH347 devices], [CH347]],
[[stlink], [ST-Link Programmer], [HLADAPTER_STLINK]],
[[ti_icdi], [TI ICDI JTAG Programmer], [HLADAPTER_ICDI]],
[[ulink], [Keil ULINK JTAG Programmer], [ULINK]],
[[usb_blaster_2], [Altera USB-Blaster II Compatible], [USB_BLASTER_2]],
[[ft232r], [Bitbang mode of FT232R based devices], [FT232R]],
[[vsllink], [Versaloon-Link JTAG Programmer], [VSLLINK]],
[[xds110], [TI XDS110 Debug Probe], [XDS110]],
[[cmsis_dap_v2], [CMSIS-DAP v2 Compliant Debugger], [CMSIS_DAP_USB]],
[[osbdm], [OSBDM (JTAG only) Programmer], [OSBDM]],
[[opendous], [eStick/opendous JTAG Programmer], [OPENDOUS]],
[[armjtagew], [Olimex ARM-JTAG-EW Programmer], [ARMJTAGEW]],
[[rlink], [Raisonance RLink JTAG Programmer], [RLINK]],
[[usbprog], [USBProg JTAG Programmer], [USBPROG]],
[[aice], [Andes JTAG Programmer], [AICE]]])
b. AC_ARG_ENABLE 部分，添加内容如下：
AC_ARG_ENABLE([ch347],
AS_HELP_STRING([--enable-ch347], [Enable building support for CH347]),
[build_ch347=$enableval], [build_ch347=no])
c. AS_IF 部分，添加内容如下：
AS_IF([test "x$build_ch347" = "xyes"], [
AC_DEFINE([BUILD_CH347], [1], [1 if you want CH347.])
], [
AC_DEFINE([BUILD_CH347], [0], [0 if you don't want CH347.])
])
d. AM_CONDITIONAL 部分，添加内容如下：
AM_CONDITIONAL([CH347], [test "x$build_ch347" = "xyes"])
修改src/jtag/interfaces.c
a. 添加编译选项
#if BUILD_CH347 == 1
extern struct adapter_driver ch347_adapter_driver;
#endif
b. 在jtag接口列表结构体adapter_drivers中添加，此处由配置脚本来启用对应接口驱动
#if BUILD_CH347 == 1
&ch347_adapter_driver,
#endif
修改/src/jtag/drivers/Makefile.am
a. 添加编译支持
if CH347
DRIVERFILES += %D%/ch347_jtag.c
endif
使用cygwin进行编译
a. 执行./bootstrap
b. 执行./configure --prefix=/home/OpenOCD/CH347 --enable-ch347 --host=i686-w64-mingw32 CFLAGS='-g -o0'
c. 执行make install
d. 编译成功时/home/OpenOCD/CH347文件夹下会生成目标文件，其中bin目录下为OpenOCD可执行文件。