(a) #PSEN (b) XTAL1 & XTAL2 (c) ALE (d) #EA
Q 2. Draw the architecture of 8051 micro-controller .Also give the features of 8051 & description of registers (DPTR, PC, A, B).
Q 3. Draw the PSW (Program Status Word) register of 8051 and describe all its bits .Also tell how register bank 3(RB3) can be selected.
Q.4 Write PUSH instructions to push the contents of the registers on stack after the execution of the following set of instructions:
MOV SP, #3FH
SETB PSW.3
MOV R0, #25H
MOV R1, #0CH
MOV R2, #05H
MOV A, #0CEH
Q 5. Write instructions to use the registers of bank 3 and load the same value 05H in the registers R0 to R3.Also tell the address where value 05H will be stored.
Q.6 Write PUSH instructions to push the contents of the registers on stack after the execution of the following set of instructions:
MOV SP, #1FH
SETB PSW.3
SETB PSW.4
MOV R0, #25H
MOV R1, #0CH
MOV R2, #05H
MOV A, #0CEH
Q 7. How a micro-controller differs from a micro-processor? Which version of micro-controller is Rom-less? Give all the major differences between 8051, 8052 and 8031 micro-controller.
Q 8. Show the contents of PSW register after the execution of the following instructions:
MOV A, #0BFH
ADD A, # 1BH
Q 9. How RAM memory space is allocated in 8051 micro-controller .Draw all the four registers banks with corresponding addresses.
Q 10. (a) Check whether the following instructions are valid or not:
1. MOV A, # 765H
2. MOV R5,# F9H
3. MOV R7, #33H
If you find any invalid statement, then give reasons for its invalidity.
(b) What do you understand by “Top of the stack”. What are the two major operations that can be performed on the stack? Give suitable