/******************************************** 
    ht9200A/ht9170程序 
    雙音多頻接收發(fā)射程序 
********************************************/ 

sbit DATA  = P3^7 ; 
sbit CLK  = P3^6 ; 
sbit CE  = P2^7 ; 

/******************************************* 
    DTMF 數(shù)據(jù)口：P0^0 ~ P0^3 
*******************************************/ 
sbit DV  = P2^6 ; 
sbit OE  = P3^2 ; 
//sbit PWDN  = P3^6 ; 
//sbit INH  = P3^7 ; 
sbit DXC  = P3^5 ; 
sbit RING = p3^0 ; 

#ifndef  TRUE 
    define     TRUE    1 ; 
#endif 
#ifndef  FALSE 
    define     FALSE    0 ; 
#endif 

uchar idata Check0 ; 
uchar idata Counter0 ; 
uchar idata Check1 ; 
uchar idata Counter1 ; 
uchar idata Check3 ; 
uchar idata Counter3 ; 

uchar code Table_DTMF[] = {0x0a,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0d,0x0e,0x0f,0x00,0x0b,0x0c} ; 
//                0    1    2    3     4    5   6    7    8    9    A    B     C    D    *    #  

void senddata_ht9200(uchar in) 
{ 
    uchar i; 
    for(i=0;i<5;i++) 
    { 
        if(((in>>i)&0x01) == 1) 
            DATA = 1 ; 
        else    DATA = 0 ; 
        CLK = 0 ; 
        CLK = 1 ; 
    } 
} 
/****************************************** 
    發(fā)送子程序 
    in 為要發(fā)送的數(shù) 0-15 
******************************************/ 
void send_ht9200(uchar in) 
{ 
    CE   = 0 ; 
    CLK  = 1 ; 
    time(50) ;            //delay about 6 ms 
    EA = 0 ; 
    senddata_ht9200(Table_DTMF[in]) ; 
    EA = 1 ; 
    delay(100) ;            //delay about 100 ms 
    CE   = 1 ; 
} 

/***************************************** 
    DTMF 讀程序 
    返回 DTMF值 
*****************************************/ 
uchar DTMF_read(void) 
{ 
    uchar TEMP ; 
    uchar i ; 
     
    EA = 0 ; 
    P0 = 0xff ; 
    OE = 1 ; 
    ACC = ACC ; 
    TEMP = P0&0x0f ; 
    OE = 0 ; 
    EA = 1 ; 
    for(i=0;i<16;i++) 
    { 
        if(TEMP == Table_DTMF[i]) 
            return i ; 
    } 
    return(0xff) ; 
} 

/****************************************** 
    初始化檢測程序 
******************************************/ 
void checkRING_Init() 
{ 
    Check0 = 2 ; 
    Counter0 = 20 ; 
} 

void checkDV_Init() 
{ 
    Check1 = 2; 
    Counter1 = 20; 
} 

void checkDXC_Init() 
{ 
    Check3 = 2 ; 
    Counter3 = 20 ; 
} 

/*************************************** 
     檢測有無振鈴RING 程序 
     返回         TRUE ：有 
               FALSE：無 
***************************************/ 
uchar check_RING(void)        // 
{ 
    uchar flag ; 
     
    flag = RING ;            //check RING 
    if((flag == 0)&&(Counter0 < 30)) 
        Counter0 ++ ; 
    if((flag == 1)&&(Counter0 > 0)) 
        Counter0 -- ; 
    if(Counter0 == 30) 
    { 
        Counter0 = 20 ; 
        if(flag != Check0) 
        { 
            Check0 = flag ; 
            return TRUE ; 
        } 
        else return FALSE;  
    } 
    else if(Counter0 == 0) 
    { 
        Counter0 = 20 ; 
        Check0 = 1; 
        return FALSE; 
    } 
    else 
        return FALSE ; 
} 

/*************************************** 
     檢測有無DTMF信號 DV 程序 
     返回         TRUE ：有 
               FALSE：無 
***************************************/ 
uchar check_DV(void)        // 
{ 
    uchar flag ; 
     
    flag = DV ;            //check DV 
    if((flag == 1)&&(Counter1<30)) 
        Counter1 ++ ; 
    if((flag == 0)&&(Counter1 >0)) 
        Counter1 -- ; 
    if(Counter1 == 30) 
    { 
        Counter1 = 20 ; 
        if(flag != Check1) 
        { 
            Check1 = flag ; 
            return TRUE ; 
        } 
        else    return FALSE ; 
    } 
    else if(Counter1 == 0) 
    { 
        Counter1 = 20 ; 
  &nbs