连线：两个单片机用3根线连起来，要共地,rxd,txd要交叉连接

程序效果：通过主机发送，从机接收

在主机中通过记下按键按下的次数，主机中显示最后

按下的六个数值，并发送给从机，从机也显示这六个数值-Connection: two microcontrollers with three lines connected together to a common ground, rxd, txd cross-linker to the effect: By sending host receiving host by noting the number of times the button is pressed　the machine, the host display and press value under six, and sent to the slave, the slave display six values