#include

#include

#define ADDR1 0x2c //MAX5820LEUA

sbit key_sin=P1^0;

sbit key_tran=P1^2;

sbit key_tooth=P1^4;

sbit SCL = P2 ^ 0;

sbit SDA = P2 ^ 1;

unsigned char code sin[256]=     //正弦表

{

0x80,0x83,0x86,0x89,0x8d,0x90,0x93,0x96,0x99,0x9c,0x9f,0xa2,0xa5,0xa8,0xab,0xae,0xb1,0xb4,0xb7,0xba,0xbc,0xbf,0xc2,0xc5,

0xc7,0xca,0xcc,0xcf,0xd1,0xd4,0xd6,0xd8,0xda,0xdd,0xdf,0xe1,0xe3,0xe5,0xe7,0xe9,0xea,0xec,0xee,0xef,0xf1,0xf2,0xf4,0xf5,

0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfd,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xfe,0xfd,

0xfd,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,0xf4,0xf2,0xf1,0xef,0xee,0xec,0xea,0xe9,0xe7,0xe5,0xe3,0xe1,0xde,0xdd,0xda,

0xd8,0xd6,0xd4,0xd1,0xcf,0xcc,0xca,0xc7,0xc5,0xc2,0xbf,0xbc,0xba,0xb7,0xb4,0xb1,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,0x99,

0x96,0x93,0x90,0x8d,0x89,0x86,0x83,0x80,0x80,0x7c,0x79,0x76,0x72,0x6f,0x6c,0x69,0x66,0x63,0x60,0x5d,0x5a,0x57,0x55,0x51,

0x4e,0x4c,0x48,0x45,0x43,0x40,0x3d,0x3a,0x38,0x35,0x33,0x30,0x2e,0x2b,0x29,0x27,0x25,0x22,0x20,0x1e,0x1c,0x1a,0x18,0x16,

0x15,0x13,0x11,0x10,0x0e,0x0d,0x0b,0x0a,0x09,0x08,0x07,0x06,0x05,0x04,0x03,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00,

0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x02,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0a,0x0b,0x0d,0x0e,0x10,0x11,0x13,0x15,

0x16,0x18,0x1a,0x1c,0x1e,0x20,0x22,0x25,0x27,0x29,0x2b,0x2e,0x30,0x33,0x35,0x38,0x3a,0x3d,0x40,0x43,0x45,0x48,0x4c,0x4e,

0x51,0x55,0x57,0x5a,0x5d,0x60,0x63,0x66,0x69,0x6c,0x6f,0x72,0x76,0x79,0x7c,0x80

};

bit write_addr(unsigned char,bit);//第一个参数表示地址，第二个参数表示 读：1 写：0

bit write_data(unsigned char);//第一个参数表示数据，第二个参数表示 命令字

void stop();

void Delay(unsigned int);

I2C_Delay(unsigned int I2C_VALUE)

{

while ( --I2C_VALUE!= 0 );

}

/*

函数：I2C_Init()

功能：I2C 总线初始化，使总线处于空闲状态

说明：在 main()函数的开始处，通常应当要执行一次本函数

*/

void I2C_Init()

{

SCL = 1;

I2C_Delay(5);

SDA = 1;

I2C_Delay(5);

}

/*

函数：I2C_Start()

功能：产生I2C 总线的起始状态

说明：

SCL处于高电平期间，当SDA 出现下降沿时启动I2C 总线

不论 SDA 和SCL 处于什么电平状态，本函数总能正确产生起始状态

本函数也可以用来产生重复起始状态

本函数执行后，I2C 总线处于忙状态

*/

void I2C_Start()

{

SDA = 1;

I2C_Delay(5);

SCL = 1;

I2C_Delay(5);

SDA = 0;

I2C_Delay(5);

SCL = 0;

I2C_Delay(5);

}

/*

函数：I2C_Write()

功能：向I2C 总线写1 个字节的数据

参数：

dat：要写到总线上的数据

*/

void I2C_Write(char dat)

{

unsigned char t = 8;

do

{

SDA = (bit)(dat & 0x80);

dat <<= 1;

SCL = 1;

I2C_Delay(5);

SCL = 0;

I2C_Delay(5);

} while ( --t != 0 );

}

bit I2C_GetAck()

{

bit ack;

SDA = 1;

I2C_Delay(5);

SCL = 1;

I2C_Delay(5);

ack = SDA;

SCL = 0;

I2C_Delay(5);

return ack;

}

void I2C_Stop()

{

unsigned int t = 10;

SDA = 0;

I2C_Delay(5);

SCL = 1;

I2C_Delay(5);

SDA = 1;

I2C_Delay(5);

while ( --t != 0 ); //在下一次产生Start 之前，要加一定的延时

}

void Delay(unsigned int I2C_Delay_t)

{

while ( --I2C_Delay_t!= 0 );

}

bit write_addr(unsigned char addr,bit mod)

{

unsigned char address;

address=addr<<1;

if(mod)

address++;

I2C_Start();

I2C_Write(address);

Delay(10);

if(I2C_GetAck())

return 1;

return 0;

}

bit write_data(unsigned char dat)

{

I2C_Write(dat);

if(I2C_GetAck())

return 1;

return 0;

}

void stop()

{

I2C_Stop();

I2C_Init();

}

void main(void)

{

unsigned char i;

loop:

I2C_Init();

while(1)

{

if(key_sin==0)        //产生正弦波

{

while(1)

{

for(i=192;i<255;i++)

{

write_addr(ADDR1,0);

write_data(0);

write_data(sin[i]);

stop();

if(!(key_tran!=0&&key_tooth!=0))

goto loop;

}

for(i=0;i<192;i++)

{

write_addr(ADDR1,0);

write_data(0);

write_data(sin[i]);

stop();

if(!(key_tran!=0&&key_tooth!=0))

goto loop;

}

}

}

if(key_tran==0)        //产生三角波

{

while(1)

{

for(i=0;i<255;i++)

{

write_addr(ADDR1,0);

write_data(0);

write_data(i);

stop();

if(!(key_sin!=0&&key_tooth!=0))

goto loop;

}

for(;i>0;i--)

{

write_addr(ADDR1,0);

write_data(0);

write_data(i);

stop();

if(!(key_sin!=0&&key_tooth!=0))

goto loop;

}

}

}

if(key_tooth==0)  //产生锯齿波

{

while(1)

{

for(i=0;i<255;i++)

{

write_addr(ADDR1,0);

write_data(0);

write_data(i);

stop();

if(!(key_tran!=0&&key_sin!=0))

goto loop;

}

}

}

}

}