How to Create Piano in Assembly Language

;
; PIANO.ASM [ - For DOS - ]
; Simple PC Speaker Piano Keyboard
; Freeware from Evenbit
;
;
.model tiny
.code
org 100h

main: jmp start
;
stor dw 0         ;our memory location storage
;
        ; Turn the cursor off.
;
start:
call curs_off           ;go turn off cursor
;
; Get a keypress from the user, and act accordingly.
; (We're checking U.S. keyboard scan codes here.)
;
get_key:
mov ah,0           ;function 0 - wait for keypress
int 16h           ;call ROM BIOS keyboard services
cmp ah,1            ;ESC key pressed?
je exit          ;yes, so go exit
cmp ah,02h
je tone_1
cmp ah,03h
je tone_2
cmp ah,04h
je tone_3
cmp ah,05h
je tone_4
cmp ah,06h
je tone_5
cmp ah,07h
je tone_6
cmp ah,08h
je tone_7
cmp ah,09h
je tone_8
cmp ah,0ah
je tone_9
cmp ah,0bh
je tone_0
;
jmp get_key          ;go get another keypress
;
exit:
call curs_on           ;go turn cursor on
int 20h       ;exit to DOS
;
tone_1:
mov ax, 272
mov stor, ax
call sounder                 ;go generate the tone
jmp get_key            ;go get another keypress
tone_2:
mov ax, 294
mov stor, ax
call sounder            ;go generate the tone
jmp get_key            ;go get another keypress
tone_3:
mov ax, 314
mov stor, ax
call sounder             ;go generate the tone
jmp get_key             ;go get another keypress
tone_4:
mov ax, 330
mov stor, ax
call sounder            ;go generate the tone
jmp get_key            ;go get another keypress
tone_5:
mov ax, 350
mov stor, ax
call sounder          ;go generate the tone
jmp get_key           ;go get another keypress
tone_6:
mov ax, 370
mov stor, ax
call sounder             ;go generate the tone
jmp get_key           ;go get another keypress
tone_7:
mov ax, 392
mov stor, ax
call sounder             ;go generate the tone
jmp get_key           ;go get another keypress
tone_8:
mov ax, 419
mov stor, ax
call sounder         ;go generate the tone
jmp get_key            ;go get another keypress
tone_9:
mov ax, 440
mov stor, ax
call sounder             ;go generate the tone
jmp get_key           ;go get another keypress
tone_0:
mov ax, 475
mov stor, ax
call sounder             ;go generate the tone
jmp get_key           ;go get another keypress



;
;****************************************
; Our sub-routines start here.
;****************************************
;
; Turn cursor off.
;
curs_off:
mov ch,10h  ;set bits to turn cursor off
mov ah,1           ;function 1 - cursor control
int 10h            ;call ROM BIOS video services
ret         ;return to caller
;
; Turn cursor on.
;
curs_on:
mov cx,0506h            ;set bits to turn cursor on
mov ah,1           ;function 1 - cursor control
int 10h           ;call ROM BIOS video services
ret           ;return to caller
;
; Generate sound through the PC speaker.
;

sounder:
mov al,10110110b         ;load control word
out 43h,al           ;send it
mov ax,stor            ;tone frequency
out 42h,al ;send LSB
mov al,ah ;move MSB to AL
out 42h,al ;save it
in al,61h            ;get port 61 state
or al,00000011b          ;turn on speaker
out 61h,al ;speaker on now
call delay ;go pause a little bit
and al,11111100b           ;clear speaker enable
out 61h,al ;speaker off now
call clr_keyb          ;go clear the keyboard buffer
ret           ;return to caller

delay:
mov ah,00h ;function 0 - get system timer tick
int 01Ah          ;call ROM BIOS time-of-day services
add dx,4          ;add our delay value to DX
mov bx,dx ;store result in BX
pozz:
int 01Ah         ;call ROM BIOS time-of-day services
cmp dx,bx ;has the delay duration passed?
jl pozz         ;no, so go check again
ret        ;return to caller
;
; Clear the keyboard buffer.
;
clr_keyb:
push es         ;preserve ES
push di          ;preserve DI
mov ax,40h ;BIOS segment in AX
mov es,ax ;transfer to ES
mov ax,1Ah ;keyboard head pointer in AX
mov di,ax ;transfer to DI
mov ax,1Eh ;keyboard buffer start in AX
mov es: word ptr [di],ax ;transfer to head pointer
inc di ;bump pointer to...
inc di ;...keyboard tail pointer
mov es: word ptr [di],ax ;transfer to tail pointer
pop di ;restore DI
pop es ;restore ES
ret         ;return to caller
;
end main
end