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

Embeded programming, i want to develop traffic light system so which kind o...

i want to develop traffic light system so which kind of software is needed to develop this project?

Scanning, how o create the flow chart for scan ROW4, Column 1 and 3.tq

how o create the flow chart for scan ROW4, Column 1 and 3.tq

Convert from C to 8086 assembly language, Trying to convert small programs ...

Trying to convert small programs from C to 8086 assembly language using emu 8086 emulator. I converted to low level C, but struggling with converting to the Assembly language.

More Sentence Sense, When Seen in the choir, Terry was the picture of an an...

When Seen in the choir, Terry was the picture of an angelic devil. I have to underline the predicate twice

Fourth generation microprocessor, Fourth  Generation Microprocessor : T...

Fourth  Generation Microprocessor : The single chip 32-bit microprocessor was introduced in 1981 by Intel as iAPX 432. The other 4th generation  microprocessors  were;  Hewlett

LC-3 Program, Write an Lc-3 assembly language program to read in a sequence...

Write an Lc-3 assembly language program to read in a sequence of single-digit positive integers from the keyboard(one integer per line) until the sentinel value of 0 is reached and

Program translation sequence, Program Translation Sequence Developing ...

Program Translation Sequence Developing a software program to accomplish a particular task, the implementer chooses an appropriate language, develops the algorithm (a sequence

Pin description of 8086-microprocessor,  Pin Description of 8086 The ...

 Pin Description of 8086 The microprocessor 8086 is a 16-bit CPU available in 3 clock rates, for example 5, 8 and 10 MHz, packaged in a40 pin CERDIP or plastic package. The 8

Neg-arithmetic intruction-microprocessor, NEG: Negate:- The negate instruc...

NEG: Negate:- The negate instruction forms the 2's complement of the particular destination in the instruction. For obtaining 2's complement, it subtracts the contents of destinat

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