Assembly Dökümanları...

[Constantin]

PUBLIC WRITE_CHAR
;................................................. ...............;
;This procedure shows the character in the computer screen using the DOS.
;................................................. ...............;

WRITE_CHAR PROC
PUSH AX ;pushes the value of the register AX in the stack memory
MOV AH,2 ;2h Function
INT 21h ;21h Interruption
POP AX ;Pops the initial value of the register AX to the register AX
RET ;Returns the control of the procedure called
WRITE_CHAR ENDP

END TEST_WRITE_HEX ;finishes the program code
Example 4
This program prints the 256 ASCII code on the screen
;name of the program: four.asm
.model small
.stack
.code

PRINT_ASCII PROC
MOV DL,00h ;moves the value 00h to register DL
MOV CX,255 ;moves the value decimal number 255. this decimal number will be 255 times to print out after the character A
PRINT_LOOP:
CALL WRITE_CHAR ;Prints the characters out
INC DL ;Increases the value of the register DL content
LOOP PRINT_LOOP ;Loop to print out ten characters
MOV AH,4Ch ;4Ch function
INT 21h ;21h Interruption
PRINT_ASCII ENDP ;Finishes the procedure

WRITE_CHAR PROC
MOV AH,2h ;2h function to print character out
INT 21h ;Prints out the character in the register DL
RET ;Returns the control to the procedure called
WRITE_CHAR ENDP ;Finishes the procedure

END PRINT_ASCII ;Finishes the program code
Example 5
This program prints a defined character using an ASCII code on the screen.
dosseg
.model small ; the name of the program is five.asm
.stack
.code
write proc
mov ah,2h;
mov dl,2ah;
int 21h
mov ah,4ch
int 21h
write endp

end write
Example 6
This program reads characters form the keyboard and prints them on the screen until find the return character.
.model small; the name of the program is six.asm
.stack;
.code;

EEL: MOV AH,01 ; 1 function (reads one character from the keyboard)
INT 21h ; 21h interruption
CMP AL,0Dh ; compares the value with 0dh
JNZ EEL ;jumps if no equal of the label eel
MOV AH,2h ; 2 function (prints the character out on the screen)
MOV DL,AL ;moves the value of the register AL to the register DL
INT 21h ;21 interruption
MOV AH,4CH ;4C function (returns the control to the DOS. operating system)
INT 21h ;21 interruption

END ;finishes the program