STC89C52驱动PT2257的示例程序

siuhiong 2012-8-22 13:41 楼主

PT2257立体声电子音量控制IC,采用I2C总线控制。下面是STC89C52单片机控制PT2257的示例程序，注意PT2257上电后需等待200ms后才可送入I2C控制信号。本程序已测试通过，并应用于某品牌卡拉OK音响系统中。

;--------------------------------
;端口及变量定义
;--------------------------------
MUSIC_SDATA    EQU    P2.2
MUSIC_SCLK    EQU    P2.1
MUSIC_VOL      EQU    60H
MUSIC_VOL1      EQU    61H
COUNTER3       EQU    62H
MUSIC_CNT        EQU    40H

;--------------------------------
;音量加大
;--------------------------------
MUSIC_UP:
    INC MUSIC_CNT
    LCALL MUSIC_PT2257
    RET
;--------------------------------
;音量减小
;--------------------------------
MIC_DN:
    DEC MIC_CNT
    LCALL MIC_PT2257
    RET
;---------------------------------
;音乐控制程序
;---------------------------------
MUSIC_PT2257:
    MOV DPTR,#VOL_TAB1
    MOV A,MUSIC_CNT
    MOV B,#2
    MUL AB
    MOV R0,A
    MOV A,B
    ADD A,DPH
    MOV DPH,A
    MOV A,R0
    MOVC A,@A+DPTR
    MOV MUSIC_VOL,A
    MOV A,R0
    INC DPTR
    MOVC A,@A+DPTR
    MOV MUSIC_VOL1,A
    LCALL START2257_MUSIC
    MOV A,#88H
    LCALL SEND2257_MUSIC
    MOV A,MUSIC_VOL
     LCALL SEND2257_MUSIC
    MOV A,MUSIC_VOL1
     LCALL SEND2257_MUSIC
    LCALL STOP2257_MUSIC
    LCALL DELAY_12M
    LCALL DELAY_12M
    RET

START2257_MUSIC:
    SETB MUSIC_SDATA
    LCALL DELAY_10
    SETB MUSIC_SCLK
    LCALL DELAY_10
    CLR MUSIC_SDATA
    LCALL DELAY_10
    CLR MUSIC_SCLK
    LCALL DELAY_10
    RET

STOP2257_MUSIC:
    CLR MUSIC_SDATA
    LCALL DELAY_10
    SETB MUSIC_SCLK
    LCALL DELAY_10
    SETB MUSIC_SDATA
    RET

SEND2257_MUSIC:
    MOV COUNTER3,#08H
SEND2257A_MUSIC:
    RLC A
    MOV MUSIC_SDATA,C
    LCALL DELAY_10
    SETB MUSIC_SCLK
    LCALL DELAY_10
    CLR MUSIC_SCLK
    LCALL DELAY_10
    DJNZ COUNTER3,SEND2257A_MUSIC
    LCALL S_ACK2257_MUSIC
    RET

S_ACK2257_MUSIC:
    SETB MUSIC_SDATA
SACK2257_MUSIC:
    LCALL DELAY_10
    SETB MUSIC_SCLK
    MOV COUNTER3,#255
SACK2257X_MUSIC:
    LCALL DELAY_10
    MOV C,MUSIC_SDATA
    JC SACK2257X_MUSIC_LOOP
    NOP
    CLR MUSIC_SCLK
    RET

SACK2257X_MUSIC_LOOP:
    DJNZ COUNTER3,SACK2257X_MUSIC
    NOP
    CLR MUSIC_SCLK
    RET

;-------------------------
;延时程序
;-------------------------
DELAY_10:
    MOV R7,#15
    DJNZ R7,$
    RET

DELAY_12M:
    MOV R7,#18H
DELAY_12M1:
    MOV R6,#0FFH
    DJNZ R6,$
    DJNZ R7,DELAY_12M1
    RET
;-------------------------
;PT2257,音乐音量表
;-------------------------
VOL_TAB1:
         DB 0FFH,0FFH

DB 0E4H,0D9H,0E4H,0D8H,0E4H,0D7H,0E4H,0D6H,0E4H,0D5H

DB 0E4H,0D4H,0E4H,0D3H,0E4H,0D2H,0E4H,0D1H,0E4H,0D0H
DB 0E3H,0D9H,0E3H,0D8H,0E3H,0D7H,0E3H,0D6H,0E3H,0D5H

DB 0E3H,0D4H,0E3H,0D3H,0E3H,0D2H,0E3H,0D1H,0E3H,0D0H
DB 0E2H,0D9H,0E2H,0D8H,0E2H,0D7H,0E2H,0D6H,0E2H,0D5H

DB 0E2H,0D4H,0E2H,0D3H,0E2H,0D2H,0E2H,0D1H,0E2H,0D0H
DB 0E1H,0D9H,0E1H,0D8H,0E1H,0D7H,0E1H,0D6H,0E1H,0D5H

DB 0E1H,0D4H,0E1H,0D3H,0E1H,0D2H,0E1H,0D1H,0E1H,0D1H
DB 0E0H,0D9H,0E0H,0D8H,0E0H,0D7H,0E0H,0D6H,0E0H,0D5H

DB 0E0H,0D4H,0E0H,0D3H,0E0H,0D2H,0E0H,0D1H,0E0H,0D0H