NOTE-The following Assembly Language Program has been prepared by our Assembly Language Programmers , just for demonstrating you the quality and comprehensiveness of our Assembly Language Homework Solutions and they do not constitute to any of our previous Assembly Language Assignment/Homework solution deliveries.
Sample Assembly Language Assignment
- Write an 80x86 assembly language program in EXE file format to do the following tasks:
- Open and read the contents of a file into memory (use at least 1 kB).
- Sort the list in numerical order using the bubble sort method.
- Display the results on the screen using the same format in (a).
- Save the output in the same file
- Uses some of the code from labs 2 and 3 as well as new code.
- Use the following procedures:
- MAIN: the main procedure.
- READ: reads the score file.
- DISPLAY: display the contents of the binary file.
- SORT: sort the entries in alphabetical order.
- ERROR: handles file errors.
- ADD_SCORE: adds a new score to the list
- SAVE: consolidates the file to only contain the scores in the list, and saves them
in order. It only saves the top 10 scores!
- All the DOS function calls used for file I/O should be added as MACROs to your
DOS.MAC file. - The high score list is organized as a singly-linked list. Each entry contains two fields:
- A pointer (offset address) to the next element. The data type is WORD (16-bit).
- The text field contains a numerical score (ASCII) followed by a ' : ', followed by a
name, and is terminated by 2 spaces (' '). The data type is BYTE. - The list should only contain 10 scores. (The file may contain more than 10)
- Each name can be limited to 5 characters.
- The score must be able to range from 0 to 16777215.
- You don’t explicitly declare a linked list in memory. You just declare a buffer
space where the linked list will be read to, added to, sorted, and written from.
StringIn MACRO in
mov ah,0AH
mov dx,offset in
int 21H
ENDM
PrintC MACRO char
mov dl,offset char
mov ah,02H
int 21h
ENDM
PrintS MACRO string
mov dx,offset string
mov ah,09h
int 21h
ENDM
PushAll MACRO ;Save all the registers
push ax
push bx
push cx
push dx
push di
push si
ENDM
PopAll MACRO ;Restore all the registers
pop si
pop di
pop dx
pop cx
pop bx
pop ax
ENDM
Return MACRO
mov ah,4CH
int 21H
ENDM
Create MACRO handle,filename
mov cx, 0
mov ah, 3ch
mov dx, offset filename
int 21h
mov handle,ax
call CheckError ;if carry set, there was an error
ENDM
Open MACRO handle,filename
mov al, 0
mov ah, 3dh
mov dx, offset filename
int 21h
mov handle,ax
ENDM
Len MACRO buff
mov cx,2 ;take into account header
mov bx, offset buff+2
call calclen
mov bx, offset buff
mov [bx],cl
ENDM
ReadFile MACRO handle,buff,size
mov ah, 3fh
mov bx, handle
mov cx, size
mov dx, offset buff
int 21h
call CheckError ;if carry set, there was an error
ENDM
WriteFile MACRO handle,buff,size
mov ah, 40h
mov bx, handle
mov dx, offset buff
mov cx, size
int 21h
call CheckError ;if carry set, there was an error
ENDM
Close MACRO handle
mov bx, handle
mov ah, 3eh
int 21h
call CheckError ;if carry set, there was an error
ENDM
InChar MACRO
mov ah,1H
int 21H
ENDM
.MODEL small
;FILENAME: Lab4.asm
;FILE FORMAT: EXE
include dos.mac
stack_seg SEGMENT stack
db 100 dup(?)
stack_seg ENDS
;EXTRA_SEG SEGMENT EXTRA
;DB 100 DUP(?)
;EXTRA_SEG ENDS
data_seg SEGMENT 'DATA'
;file MUST be at the start of data segment
;since it replicates the contents of the file
;format of data
;dw pointer to next (or 0 at end)
;db score ':' name ' ' (2 spaces)
head db 2,0 ;first entry
scr1 db ?,?,"998:JEANE "
scr2 db ?,?,"999:BILLY "
scr3 db ?,?,"16777215:DAVID "
db 0,0 ;end of sample data
endinit db 4096 dup(0)
endoffile db 0
hs db 0DH,0AH,"The high scores are: ",0DH,0AH,'$'
prmpt db 0DH,0AH, "Do you want to:",0DH,0AH
db "a. Add a new score to the list?",0DH,0AH
db "b. Exit ",0DH,0AH
db '$'
errprmpt db 0DH,0AH, "Choice unacceptable. $"
fileerr db 0DH,0AH, "Problem with file. $"
filename db "score.bin",0
handle dw 0
topten dw 0
endline db 10,13,'$'
char db ?
nmin db 6,?,6 dup(?) ;6 characters
scrin db 9,?,9 dup(?) ;9 characters
nmprmpt db 0DH,0AH, "Enter Name: $"
scrprmpt db 0DH,0AH, "Enter Score: $"
bye db 0DH,0AH, "Bye $"
err02 db "File not found$"
err03 db "Path not found$"
errcode db ?
swapped db ?
tmp db ?
data_seg ENDS
code_seg SEGMENT para 'CODE'
assume CS:code_seg, DS:data_seg, SS:stack_seg
main PROC far
mov ax,data_seg
mov ds,ax
mov ax,stack_seg
mov ss,ax
mov ax,data_seg ;extra_seg
mov es,ax ;initialize segments
call read ;read file (create if not present)
start:
prints hs
over:
call sort ;sort by score
call displayfile ;display names
prints prmpt
InChar
mov char,al
cmp char,'a'
je @a
cmp char,'b'
je @b
jne @x
@a:
call addScore ;add new entry
jmp start
@b:
prints bye
jmp done
@x:
prints errprmpt
jmp over
done:
call save
.exit
main ENDP
save PROC near
mov bx,offset head
mov ax,[bx]
mov bx,ax ;go to 1st entry
mov cx,10 ;top 10 only
saveloop:
mov ax,[bx]
and ax,ax
je endfile ;we reached 0
add ax,offset head
mov bx,ax
dec cx
je endfile ;maximum of 10 entries
jmp saveloop
endfile:
mov word ptr [bx],0 ;if we have more than 10, stop here
sub word ptr bx, offset head
add bx,2 ;to account for the 0 at the end of file
mov topten,bx
create handle,filename ;create dummy file
WriteFile handle,head,topten
close handle
RET
SAVE ENDP
;bx points to 1st pointer
;di points to 2nd pointer
;[bx] should be larger than [di]
;returns ax != 0 if swap, else ax = 0
compare PROC near
push bx
push di
add bx,2
add di,2 ;skip pointer
;First find longest number, it must be larger
;Search for :
mov cl,':'
.findcolon:
mov al,[bx]
mov dl,[di]
inc bx
inc di
cmp al,cl
je .len ;possible the same length
cmp dl,cl
JE .NOSWAP
JMP .FINDCOLON
.LEN:
CMP DL,CL
JNE .SWAP
;Must be the same length
POP DI
POP BX
PUSH BX
PUSH DI
;Now we need the data again
ADD BX,2
ADD DI,2
.CMPLOOP:
MOV AL,[BX]
MOV DL,[DI]
CMP AL,CL
JE .NOSWAP ;Reached : must be the same number
INC BX
INC DI
CMP AL,DL
JC .SWAP
JMP .CMPLOOP
.NOSWAP:
POP DI
POP BX
MOV AX,0 ;No Swap
RET
.SWAP:
POP DI
POP BX
MOV AX,1
RET
COMPARE ENDP
READ PROC NEAR
OPEN handle,filename
;UNABLE TO FIND FILE, CREATE IT
JC NOFILE
ReadFile handle,head,endoffile-head
CLOSE handle
RET
READ ENDP
NOFILE PROC NEAR
LEN scr1 ;Find the length
LEN scr2
LEN scr3
mov al,[scr1] ;Calculate links
add al,2
mov [scr1],al
mov bl,[scr2]
add al,bl
mov [scr2],al ;for each score
mov bl,[scr3]
add al,bl
mov [scr3],al ;using length
CREATE handle,filename ;create dummy file
WriteFile handle,head,endinit-head
CLOSE handle
RET
NOFILE ENDP
CheckError:
jc Error ;If carry flag set, then error
ret
ERROR PROC NEAR
mov errcode,al
PRINTS fileerr
cmp errcode,2
jne noterr2
PRINTS err02
noterr2:
cmp errcode,3
jne noterr3
PRINTS err03
noterr3:
JMP done
ERROR ENDP
DISPLAYFILE PROC NEAR
mov bx,offset head
mov ax,[bx]
mov bx,ax ;go to 1st entry
displayloop:
mov ax,[bx]
and ax,ax
je enddisplay ;we reached 0
add ax,offset head
push bx ;save current pointer
add bx,2 ;skip pointer value
mov dx,bx ;dx = start of string
;find the end of string and add $ to it
.findend:
mov ah,[bx]
inc bx
cmp ah,' '
jne .findend ;loop until we find a space
mov ah,[bx]
cmp ah,' ' ;was it double space
jne .findend ;nope
mov byte ptr [bx],'$' ;add end of string
MOV AH,09
INT 21h
mov byte ptr [bx],' ' ;remove end of string
pop bx ;restore current pointer
PRINTS endline
mov ax,[bx]
mov bx,ax
jmp displayloop
enddisplay:
ret
DISPLAYFILE ENDP
CalcLen PROC NEAR
mov al,[bx]
inc cx
inc bx
cmp al,' ' ;ends with double space
jne CalcLen
mov al,[bx]
inc cx
inc bx
cmp al,' ' ;ends with double space (this is 2nd)
jne CalcLen
ret
CalcLen ENDP
;void sort()
;{
; bool swapped = true;
; while (swapped)
; {
; swapped = false;
; Item *prev = &root;
;
; Item *curr = root.next;
; Item *next = curr->next;
;
; while (next)
; {
; if (next->score > curr->score)
; {
; prev->next = next;
; curr->next = next->next;
; next->next = curr;
; swapped = true;
; }
; prev = curr;
; curr = next;
; next = next->next;
; }
; }
;}
SORT PROC NEAR
; bool swapped = false;
mov [swapped],0
; Item *prev = &root;
mov si,offset head
; Item *curr = root.next;
mov bx,[si]
; Item *next = curr->next;
mov di,[bx]
; while (next)
.while:
; if (next->score > curr->score)
PushAll
call compare
mov [tmp],al
PopAll
mov al,[tmp]
and al,al
je .nosortswap
; prev->next = next;
mov [si],di
; curr->next = next->next;
mov ax,[di]
mov [bx],ax
; next->next = curr;
mov [di],bx
; swapped = true;
mov [swapped],1
jmp sort ;pointers are modified, restart
.nosortswap:
; prev = curr;
mov si,bx
; curr = next;
mov bx,di
; next = next->next;
mov ax,[di]
; while (next)
mov di,ax
mov ax,[di]
and ax,ax
jne .while
; while (swapped)
mov al,[swapped]
and al,al
; jne sort
ret
SORT ENDP
ADDSCORE PROC NEAR
PRINTS nmprmpt
STRINGIN nmin
PRINTS scrprmpt
STRINGIN scrin
mov bx,offset head
addscoreloop:
mov ax,[bx]
and ax,ax
je addscoreend ;we reached 0
add ax,offset head
mov bx,ax
jmp addscoreloop
addscoreend:
mov ax,bx
mov cx,0
mov cl,[nmin+1]
add ax,cx
mov cl,[scrin+1]
add ax,cx
add ax,5 ;for : 2 spaces and 0
mov [bx],ax
add bx,2
mov cx,offset scrin
call copystr
mov byte ptr [bx],':'
inc bx
mov cx,offset nmin
call copystr
mov byte ptr [bx],' '
inc bx
mov byte ptr [bx],' '
inc bx
mov byte ptr [bx],0
inc bx
mov byte ptr [bx],0
RET
ADDSCORE ENDP
;copys a string from cx to bx, cx[1] has the length
copystr proc near
mov di,cx
inc di ;size of buffer
mov dl,[di]
inc di ;count
.loop:
mov al,dl
je .ret
mov al,[di]
inc di
mov [bx],al
inc bx
dec dl
jmp .loop
.ret: ret
copystr endp
CODE_SEG ENDS
END MAIN