A.0,90,0,0,-90,0B.0,-90,180,0,90,0C.0,90,90,90,-90,90D.90,0,0,0,-90,0
A.外夹式B.内夹式C.内撑式D.外撑式
A.数字信号的输入输出B.模拟信号的输入输出C.所有信号的输入输出D.ABC 都不对