A.多路開關后,A/D轉換前 B.多路開關前,A/D轉換前 C.多路開關后,A/D轉換后 D.A/D轉換后,多路開關前
A.1/8 B.1/128 C.1/256 D.1/512
A.TxD B.RxD C.CTS D.RTS