Difference between revisions of "CSC231 Homework 7 2014"
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| − | * Write a function called '''printInt16''' that prints a 16-bit 2 | + | * Write a function called '''printInt16''' that prints a 16-bit 2's complement number on the screen. |
* Your function should work similarly to '''printInt''', but the number it prints is the number passed in '''ax''' (not eax). | * Your function should work similarly to '''printInt''', but the number it prints is the number passed in '''ax''' (not eax). | ||
* Your function should '''not modify any of the registers''', including ax or the upper part of eax. | * Your function should '''not modify any of the registers''', including ax or the upper part of eax. | ||
Revision as of 10:39, 11 November 2014
--D. Thiebaut (talk) 10:33, 11 November 2014 (EST)
Page under construction
This assignment is due on 11/18/14, at 11:55 p.m.
Problem #1
- & Use the 231Lib.asm library as inspiration and write a function called printInt that prints a 32-bit 2-s complement number on the screen.
- Your function should work similarly to printDec, in that the number to print is passed through eax, and not through the stack!
- Your function should not modify any of the registers, including eax.
- Your function should be made global so that a test program can call it.
- Submit your function in a program called Hw7_1.asm.
Example Test Program
section .text
extern printInt
_start:
mov eax, 0
call printInt ; prints 0
mov eax, 0xff
call printInt ; prints 255
mov eax, -1
call printInt ; prints -1
mov eax, 0xffffffff
call printInt ; prints -1
mov eax, 1
mov ebx, 0
int 0x80
Problem #2
- Write a function called printInt16 that prints a 16-bit 2's complement number on the screen.
- Your function should work similarly to printInt, but the number it prints is the number passed in ax (not eax).
- Your function should not modify any of the registers, including ax or the upper part of eax.
- Your function should be made global so that a test program can call it.
- Submit your function to Moodle in a program called Hw7_2.asm.
Example Test Program
section .text
extern printInt16
_start:
mov ax, 0
call printInt16 ; prints 0
mov ax, 0xff
call printInt16 ; prints 255
mov eax, 0x0000ffff
call printInt16 ; prints -1
mov eax, 0xffff0001
call printInt16 ; prints 1
mov eax, 1
mov ebx, 0
int 0x80
