实现基于tcp/ip协议的上位机client客户端功能，可以实现下位机有以太网接口的嵌入式系统与PC机的数字通信，达到测试嵌入式系统以太网功能的目的-Based on tcp/ip protocol client PC client function, can be achieved under the bit machines have Ethernet interface of embedded systems and PC-digital communications, to test e