上面是sp3539的底层函数包，主要是进行扩展串口SP3539的初始化及发送控制。对于试用SP3539采集数据的程序员来说，微微修改下就可以了-Is above the bottom of sp3539 function package, mainly for the expansion of serial SP3539 initialization and send control. SP3539 trial data collection for the programmers, can b

89c51最小系统和8155扩展和串口 protel pcb图，对初学者很有帮助-89C51 minimum system and 8155 extension and serial Protel PCB diagram, very helpful for beginners