问题
单项选择题
一系统中采用8255A作I/O接口，初始化时CPU访问其08BH端口，将它设定方式 0输入，则A口的地址为( )。
A．088H
B．089H
C．08AH
D．08CH
答案
参考答案：A
解析： 8255芯片内部寄存器地址分配从小到大为A、B、C控制寄存器，故A口地址为088H。
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一系统中采用8255A作I/O接口，初始化时CPU访问其08BH端口，将它设定方式 0输入，则A口的地址为( )。
A．088H
B．089H
C．08AH
D．08CH
参考答案：A
解析： 8255芯片内部寄存器地址分配从小到大为A、B、C控制寄存器，故A口地址为088H。
Once an Arab was traveling in the desert. When the sun went down in the west, he stopped and _36_ his tent then, made a fire and have a _37_ meal. When night fell, he_38_ down to sleep. He had_39_ fallen asleep when he felt a soft _40_ on his elbow(手肘). He woke up to find that his camel had put his head inside the tent. The camel said: “Would you please let me keep my head in the tent to get warm? It is so cold outside. I will not take up too much 41 .” The Arab was a 42 man, “All right, do as you 43 .” he said. Then he turned on his _44_ and went back to sleep. It wasn’t long 45 he felt a push on his shoulder. It was the camel again. “Dear master,” the camel said, “my head is quite warm now, but my neck is still cold. Do you mind 46 I keep it inside the tent, too?” “ _47_ .” the man said. But this time he felt a bit 48 , as camel had such a long neck. No sooner had he shut his eyes 49 he got a harder push in his side. This time the camel said, “will you please allow me to bring my front legs inside and warm then a little?” The Arab_ 50_ over to one side of the tent. He made _51_ as small as he could. It was not _52_ comfortable, and sleep was now out of 53 .Soon after that the camel gave his a rough push and said, “The tent is too small for the two of us. 54 , my two hind legs are still left in the cold. It is only_55_ that you should leave the tent wholly to me.” And with that, the camel kicked the poor man out.
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