I/O设备接口是主机与设备通信的桥梁，当主机采用RS 232C接口与设备通信时，设备接口除包括一般功能外，电路中还必须包含（）电路。
A. 指令译码
B. 数据格式串/并行转换
C. 地址选择
DMA控制
1．有人认为高科技显著改善了人们的生活；2．有人认为高科技给人类生活带来了一系列灾难性的后果；3．谈谈你的看法。 The Effects of High Technology
What does the woman suggest（）
A. They don’t go to the concert.
B. The subway is fine for her.
C. His brother will let them use the car.
D. They’ll rent a car.
Why does the man phone the woman（）
A. To see if she has received the samples.
B. To invite her to visit his company.
C. To tell her he had sent her some samples.
D. lb make an appointment with her.
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