5402 dsp入门程序，全部通过编译，十分方便-5402 dsp entry process, all through the compiler, which is very convenient

DSP开发板相关——合众达公司，SEED-DM642 开发板硬件led存储测试源代码-DSP development board-related- of the company union, SEED-DM642 development board hardware store to test the source code led

本程序代码是使用I2C通信的一个例子，主要实现I2C与在读写模式下的PCF8574通信。-I2C communication with a PCF8574 in read and write mode is demonstrated. PCF8574 port P is configured with P0-P3 input, P4-P7. Read P0-P3 input data is written back to Port P4-P7. This example uses t