Question

please solve question 4 quickly

MOV SP, #35H PUSH 50H PUSH 53H POP ACC MOV A, SP (ACC)- (4) How does ACC change? (5pt) ORG 3388H MOV SP, #30H LCALL SU (ACC)- SU: POP ACC POP ACC (5) Show how the value of ACC changes: (5pt) MOV A. #05H MOVCA. A PC SJMP SK DB 62H, OC2H, 99H DB 2BH, 18H (ACC) DI

Answer 1

ORG 3388H- ORIGIN ADDRESS 3388

MOV SP,#30H- MOVE IMMEDIATE DATA 30H TO STACK POINTER

LCALL SU- LONG CALL THE LOCATION SU

POP ACC-POP STACK VALUE TO THE ACCUMULATOR

HERE THE STACK POINTER IS AT 30H. AFTER THE FIRST POP INSTRUCTION, THE VALUE FROM STACK LOCATION 30H WILL BE COPIED TO THE ACCUMULATOR AND THE STACK POINTER WILL BE DECREMENTED BY 2. SO IN NEXT POP INSTRUCTION, THE VALUE IN STACK, POINTED BY THE STACK POINTER ie, (LOCATION 28) WILL BE COPIED TO THE ACCUMULATOR.

SO THE VALUE IN ACC WILL BE THE VALUE IN STACK LOCATION 28H.

(The value in stack location 28H and 30H is not given in the question)