MPU 2ND Test

GROUP - A [ ANSWER ALL QUESTIONS ] [ MARKS - 8 ]

1) Discuss the function of RS0 & RS1 bits in PSW.
2) What is the function of following pins in 8051?
(i) PSEN (ii) TXD
3) Enlist all the instructions that use Stack Memory.
4) What are the function of the assembler & linker?
5) Why is a register different from a memory location?
6) When is it required to use the control signals WR & RD?
7) What happens in the following instructions –
(i) INC @R3 (ii) CPL 91H (iii) MOV SP, #74H
8) What is the range of AJMP instruction for transferring the control?
9) How many types of Addressing modes are there in 8051? Name them.
10) What is the range of address that can be addressed with register indirect addressing in external data RAM?
11) Give a example of Data Transfer Instruction with Index Addressing.
12) What are the addresses of Bit Addressable location?
13) What do you mean by SFR & what is the range of address?
14) What is the difference between overflow (OV) and carry flag (C)?
15) Why the Program Counter (PC) and Data Pointer Register (DPTR) of 8051 is 16 – bit wide, whereas the stack pointer register is of 8- bit wide only ? Justify.


16) Write a sequence of instructions that sets the AC flag?
17) List out four instructions that access only the Bitwise Operand.
18) Explain the difference between MOVX and MOV instruction.
19) What is the value of EA when the Internal Program Memory is accessed?
20) List all the Special Function Register in 8051, find out their address.
GROUP - B [ COMPULSORY ] [ MARKS – 2 ]

1) Write an Assembly Language Program to obtain the Decimal equivalent of an 8-bit Hexadecimal number stored in given memory location. Store the result in three consecutive memory location , they are 4501H,4502H & 4503H.
Hex Number is stored in
[4500] = FFH