Arm调试中实现串口重定向功能，将串口输出的八进制数据转换成 d s等任意模式-Serial port retarget

该代码为VHDL语言描述的AD7738串口通讯程序，示例为双通道单独转换模式，其它可以根据注解类推。-This is a serial communication promgram of AD7738 designed with VHDL,which is two-channel mode, other modes can be deduced by interprecation.

该代码为VHDL语言描述的DAC7644串口通讯程序，示例为通道0单独转换模式，其它通道可以类推-Thisis a serial communication promgram of DAC7644 designed with VHDL,which is output of channel 0, other channels can be deduced.