已知单片机的晶振频率为6MHz，下面程序用单片机内部定时器T0工作在方式1下，从P1.0输出周期为______的方波脉冲信号，时间常数为______。ORG 3000H START：MOV TMOD, #01HMOV TL0,#OCHMOV THO, #OFEHSETB TR0 LOOP： JBC TFO,DONESJMP LOOP DONE：MOV TL0,#OCHMOV THO，#OFEHCPL P1.0SJMP LOOP
参考答案：2ms OFEOCH
解析：注意这里是16位定时计数器。
| 阅读短文，从各题所给的四个选项中，选出 一个正确答案。 | ||||
| Once there was a king who told some of his people to dig a pond (池子). The king then told his people that one person 1 each family had to bring a glass of milk during the night and put it into the pond. So, by the morning, the pond should be 2 of milk. After 3 the order, everyone went home. As one man prepared his milk, he thought that since everyone was bringing milk, he would just 4 a glass of water and put that into the pond instead. 5 it was dark at night, no one would notice it, so he quickly went and put the water into the pond and 6 home. In the morning, the king went to visit the pond. To his 7 , the pond was only filled with water! What happened? Yes! Everyone had the same idea 8 that man. They all thought, "I don't have to waste my milk. Someone else will do it. " Dear friends, when you plan to help poor people or people in trouble, do not think that 9 will take care of it. Instead, it starts with you. If you don't do it, no one else will, so change yourself and make a 10 . | ||||
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