A.11 B.110 C.10 D.100
MCS—51單片機(jī)串行口接收數(shù)據(jù)的次序是下述的順序(). (1)接收完一幀數(shù)據(jù)后,硬件自動(dòng)將SCON的R1置1 (2)用軟件將RI清零 (3)接收到的數(shù)據(jù)由SBUF讀出 (4)置SCON的REN為1,外部數(shù)據(jù)由RXD(P3.0)輸入
A.(1)(2)(3)(4) B.(4)(1)(2)(3) C.(4)(3)(1)(2) D.(3)(4)(1)(2)
A.TTL電平 B.RS232C電平 C.RS422電平 D.RS485電平