利用51的两个输入输出引脚如P1.0和P1.1，置1或0分别代表高低电

平，也就是串口通信中所说的位，如起始位用低电平，则将其置0，停止位为高电平，则将其置

1，各种数据位和校验位则根据情况置1或置0。-Using 51 as the two input and output pins P1.0 and P1.1, set to 1 or 0 representing the high and low, that is said in the bit serial communication, such as the use of low starting position, will be its set to 0, stop bit is high, then it is set to 1, all data bits and the parity bit set to 1 according to the situation or set to 0.