Page 180 - DCAP210_INTRODUCTION__TO_MICROPROCESSORS

Introduction to Microprocessors

Notes 3. ………… operation perform the insertion on stack.

(a) POP (b) PUSH
(c) INSERT (d) None
4. ………… operation perform the deletion on stack.

(a) POP (b) PUSH
(c) INSERT (d) None
5. The 8085 uses a 16 bit register to know where the stack top is located, and that register is
called the………….
(a) TOP (b) Overflow
(c) INSERT (d) Stack Pointer

6. The condition on which no any data can be insert in stack is called………
(a) underflow (b) overflow
(c) insert (d) stack Pointer

7. The condition on which no any data can be delete from stack is called………
(a) underflow (b) overflow
(c) insert (d) stack Pointer
8. Stacks were also used as a basis of a number of mainframes and mini computers.

(a) True (b) False

12.8 Review Questions

1. What is Stack Pointer?

2. Which Stack is used in 8085?
3. Read the following program and answer the questions:
4000 LXI SP, 4100H DELAY : 4064 PUSH H
4003 LXI B, OOOOH 4065 PUSH B

4006 PUSH B , 4066 LXI B, 80FFH
4007 POP PSW LOOP : 4069 DCX B
4008 'LXI H, 400BH 406A MOV A, B

400B CALL 4064H 406B ORA C
400E OUT 01H 406C JNC LOOP
4010 HLT 406F POP B
4070 RET

(a) What is the status of the flags and the contents of the Accumulator after the execution
of the POP instruction located at 4007H?

(b) Specify the stack locations and their contents after the execution of the CALL instruction
(not the call subroutine)
(c) What are the contents of the stack pointer register and the program counter?

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