查询方式接收串口数据，程序要不断地查询中断标志位TCON.URX0IF是否为1。
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Tom is my roommate. He usually _____ at 7:40, but yesterday he _____ at 6:00.
A. get up; got up
B. gets up; got up
C. got up; gets up
D. got up; get up
He _____ in Beijing now, but 5 years ago he _____ in New York.
A. lived; live
B. live; lived
C. lives; lived
D. lived; lives
He first _____ his wife when theyboth _____ in Beijing.
A. meets; are
B. met; are
C. meets; were
D. met; were
When he was in the army, he _____ a uniform every day.
A. wears
B. wore
C. was wearing
D. worn
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