ECE391_Homework_2_Semester3.docx - Ho Chi Minh City...

Ho Chi Minh City University of Technology Department of Electronics and Electrical
Engineering
ECE391: Computer System Engineering
Homework 2
1. For each part of this problem, answer the value of registers after the instruction is
executed.
No. Before Instruction After
1 BX: FF 75
CX: 01 A2
mov bx, cx BX:
CX:
2 AX: 01 A2 mov ax, 100 AX: ?
3 EDX: FF 75 4C 2E
Value: DWORD 1
mov edx, Value EDX: ?
Value: ?
4 AX: 01 4B mov ah, 0 AX: ?
5 EBX: 00 00 3A 4C
Value: DWORD ?
mov Value, ebx EBX: ?
Value: ?
6 EBX: FF FF FF 75
ECX: 00 00 01 A2
add ebx,ecx EBX, ECX, SF, ZF, CF,
OF
7 EBX: FF FF FF 75
ECX: 00 00 01 A2
sub ebx,ecx EBX, ECX, SF, ZF, CF,
OF
8 BX: FF 75
CX: 01 A2
sub cx,bx BX, CX, SF, ZF, CF, OF
9 EAX: 00 00 00 64 sub eax,100 EAX, SF, ZF, CF, OF
10 AX: 0A 20 add ax,Value AX, SF, ZF, CF, OF
2. Write a complete 80x86 assembly language program to prompt for values of x, y, and z
and display the value of the expression x*2y + 4z. Allow for 16-bit integer values.
3. Assume for each part of this problem that the EAX register contains 00 00 00 4F and the
doubleword referenced by value
?
?
word at Value: FF 20