单片机接收主机的数据,然后将数据传送到P0口, 并传回给主机 当按下K1=P1.4 时, 单片机发送字www.pp51.comr" 给主机-Microcontroller to receive the host data, and then transfer data to P0 port, and returns to the host when you press K1 = P1.4, the microcontroller sends word www.pp51.comr &quo