Music Box developed by single chip microcomputer (Happy birthday)

 

 

Seven speakers-Happy Birthday.

Org 0000 h
Ajmp main
Org 000bh
JMP tim0
Org 0030 H
 
; Main program
Main: mov tmod, #01 H; set the time mode
MoV IE, #82 h; on interrupt
Start0: mov 30 h, #00 h;
Next: mov A, 30 h
MoV dptr, # Table
Movc A, @ A + dptr; look up the table to take the tone and beat
MoV R2,
JZ end0; 0, not processed.
Anl a, # 0fh
MoV R5, A; store the beats to R5
MoV A, r2
Swap
Anl a, # 0fh
Jnz sing; determines whether to play based on the tone.
CLR tr0
JMP d1
Sing: Dec
MoV 22 h, A; Save the tone to 22 h.
RL
MoV dptr, # Table1
Movc A, @ A + dptr; determine the initial timer value based on the tone.
MoV th0, A; put th0
MoV 21 h,
MoV A, 22 h
RL
INC
Movc A, @ A + dptr
MoV tl0, A; put in tl0
MoV 20 h,
SETB tr0; Start Time
D1: Call Delay
INC 30 h
JMP next
End0: CLR tr0
JMP start0

; The timer interrupts the service program.
Tim0: Push ACC
Push psw
MoV tl0, 20 h; re-assigned initial value.
MoV th0, 21 h
Cpl limit 7
Pop psw
Pop ACC
RETI

Delay: mov R7, #02 h; latency subroutine
D2: mov R4, #187
D3: mov R3, #248
Djnz R3, $
Djnz R4, D3
Djnz R7, D2
Djnz R5, delay
RET

Determine the initial value of the tone.
Table1: DW 64260,64400, 64524,64580
DW 64684,64777, 64820,64898
DW 64968,30,58,65110
DW 65157,65178, 65217

The table that determines the tone and the beat. Different songs are only different in this table.

Table: DB 82 H, 01 H, 81 h, 94 H, 84 h, 0b4h, 0a4h, 04 H, 82 H, 01 H, 81 h, 94 H, 84 h, 0c4h, 0b4h, 04 H; 1
DB 82 H, 01 H, 81 h, 0f4h, 0d4h, 0b4h, 0a4h, 94 H, 0e2h, 01 H, 0e1h, 0d4h, 0b4h, 0c4h, 0b4h, 04 H; 2
DB 82 H, 01 H, 81 h, 94 H, 84 h, 0b4h, 0a4h, 04 H, 82 H, 01 H, 81 h, 94 H, 84 h, 0c4h, 0b4h, 04 H; 3
DB 82 H, 01 H, 81 h, 0f4h, 0d4h, 0b4h, 0a4h, 94 H, 0e2h, 01 H, 0e1h, 0d4h, 0b4h, 0c4h, 0b4h, 04 H, 00; 4
End