Some single-chip computers can answer questions that the owner can answer.

Too many. I suggest reading.

2. Briefly describe the meaning of symbols CY and OV. Why does overflow happen? What is the essence of overflow?

5 1 series single chip microcomputer is an eight-bit computer, and every calculation operation is carried out on eight digits.

Eight-bit binary numbers are added. When carried to the ninth place as 1, Cy is 1, otherwise it is 0.

If there is a borrow in subtraction, Cy will be 1, otherwise it will be 0.

The signed number is represented by an eight-bit binary number, and its value range is:-128 ~+ 127.

When the operation result exceeds this range, OV is 1, otherwise it is 0.

1 1. Write the addressing method of the source operand in the following instructions.

1) MOV A, R3- register

2) movptr, # 1 100h- count immediately.

3) MOV C, 30h- direct

4) MOV A, 40h- same as above

5) MOV A, R0- register

6) movca, @ a+dptr- relative

7) movxa, @ dptr- registration indirect

19. What is the function of the pseudo instruction END? Can you let the program end normally?

Notifies the compiler that compilation is over.

Unable to make the program end normally.

27. Can the interrupt of MCS-51be shielded?

Yes, let EA be 0.