StrNCpyAsm, Assembly Language

Assignment Help:
;StrNCpyAsm - copy zero terminated string2 to zero terminated string1,
; but copy no more than count (parameter) characters
; or the length of string2, whichever comes first
; entry: - addStr1 contains the address of string1
; - addStr2 contains the address of string2
; - count contains the max number of characters to copy
; exit: NONE (no return value so do not use edi to return an address)
;
; Note: StrNCpyAsm does not zero terminate the copied string
; unless the 0 is within count characters copied.
;
; example1: char str1[]= {''h'',''e'',''l'',''l'',''o'','' '',''w'',''o'',''r'',''l'',''d'',0};
; char str2[]= {''G'',''o'',''o'',''d'',''-'',''b'',''y'',''e'',0};
; StrNCpyAsm(str1,str2,4);//terminating 0 not copied since only 4 characters copied
; ;//and terminating 0 not within the 4 characters
; after copy str1 contains: ''G'',''o'',''o'',''d'',''o'','' '',''w'',''o'',''r'',''l'',''d'',0
;
; example2: use str1 and str2 from example1
;
; StrNCpyAsm(str1,str2,9); //terminating 0 copied since terminating 0
; //within 9 characters copied
; str1 contains: ''G'',''o'',''o'',''d'',''-'',''b'',''y'',''e'',0,''l'',''d'',0
;
; example3: use str1 and str2 from example1
;
; StrNCpyAsm(str1,str2,20);//copy 20 characters upto and including 0,
; //whichever comes first
; //only 9 characters including 0 copied
; after copy str1 contains: ''G'',''o'',''o'',''d'',''-'',''b'',''y'',''e'',0,''l'',''d'',0
;
; The above is how you would call StrNCpyAsm from C++.
;
; To call StrNCpyAsm from an asm function use:
;
; push 20 ;max num of characters to copy
; push str2Add ;address of string 2
; push str1Add ;address of string 1
; call StrNCpyAsm
; ;no add esp, 12 needed because stack cleaup automatically done
;
;Do not use a loop in this function.
;Choose 2 instructions from the following string instructions to use:
; rep, repe, repne, movsb,stosb,cmpsb,scasb
;
; hint1: use StrLenAsm to get the number of characters in str2
; hint2: the length returned by StrLenAsm does not include terminating 0
; hint3: copy the lesser of the length of the string (including terminating 0)
; or count characters
;copy to ecx the lesser of count or the length of string2 (including terminating 0)
; Please note for the above, you need the length of string2 including terminating 0.
; StrLenAsm returns the length not including terminating 0
;populate esi and edi with the correct values
;clear the direction flag
;use rep and movsb to copy
;
;

StrNCpyAsm PROC uses eax esi edi ecx , ;save registers used
addStr1:DWORD, ;address of string1
addStr2:DWORD, ;address of string2
count:DWORD ;max chars to copy

Related Discussions:- StrNCpyAsm

Lds/les instruction execution-microprocessor, LDS/LES Instruction execution...

LDS/LES Instruction execution :  LAHF : Load AH from Lower Byte of Flag: - This instruction loads the AH register with the lower byte of the flag register. This instruction ca

Program on virtual learning environment, Task One Produce a menu such a...

Task One Produce a menu such as the one below (remember to keep to this specification). M E N U 1, Enter Number 1 2, Enter Number 2 3, Display num1 and num2 4, D

Third generation microprocessor, III rd Generation Microprocessor: T...

III rd Generation Microprocessor: The single 3rd generation microprocessor chip having 64-pins began with the introduction of 16-bit Intel 8086 in 1978. The other essential

Program to add 8-bit series numbers-assembly language, Program: Write a pr...

Program: Write a program to perform addition of a series of 8-bit numbers. The series have 100 (numbers). Solution : In the first program, we have been implemented the add

Read file in 8086, Write a procedure to read a text file and copy its cont...

Write a procedure to read a text file and copy its contents to another text file using 8086 assembly language .

Program to move contents in memory-machine level programs, Example : Write...

Example : Write a program to move the contents of the memory location 0500H to BX and also to register CX. Add immediate byte 05H to the data residing in memory location, whose ad

Assignment, You have to write a subroutine (assembly language code using NA...

You have to write a subroutine (assembly language code using NASM) for the following equation.

Programming, Using the following table as a guide, write a program that ask...

Using the following table as a guide, write a program that asks the user to enter an integer test score between 0 and 100. The program should display the appropriate letter grade.

Write an assembly language program to fi nd the maximum, Write an assembly ...

Write an assembly language program to find the maximum of: y = x 6 - 14x 2 + 56x for the range -2 ≤ x ≤ 4, by stepping one by one through the range. The program should in

Using straight line method for depreciation, Request a depreciation of the...

Request a depreciation of the item, year of purchase, cost of item, number of years to be depreciated (estimated life ) and,the method of depreciation . Method of depreciation sh

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd