dac7724和28335怎么接线

可以选用两个IO口进行控制，LADC主要作用是当其为低电平时，四个输出通道都处于Transparent模式，而当前为高电平时，可以根据A0，A1，RW,CS的状态来选择某个输出通道的寄存器为Transparent或者readback模式，建议仔细阅读datasheet的第14页来了解这几位的功能，至于RESET，其功能就是置低时复位所DAC内部寄存器。

sbit wr=P3^6

sbit rd=P3^2

sbit k0=P1^0

sbit k1=P1^1

sbit k2=P1^2

sbit k3=P1^3

sbit k4=P1^4

unsigned char flag//当flag为0、1、2、3、4时分别产生正弦波、方波、三角波、梯形波、锯齿波

unsigned char const code sin_code[256]={

0x80,0x83,0x86,0x89,0x8c,0x8f,0x92,0x95,0x98,0x9c,0x9f,0xa2,

0xa5,0xa8,0xab,0xae,0xb0,0xb3,0xb6,0xb9,0xbc,0xbf,0xc1,0xc4,

0xc7,0xc9,0xcc,0xce,0xd1,0xd3,0xd5,0xd8,0xda,0xdc,0xde,0xe0,

0xe2,0xe4,0xe6,0xe8,0xea,0xec,0xed,0xef,0xf0,0xf2,0xf3,0xf4,

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

0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xfe,0xfe,

0xfd,0xfc,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,0xf3,0xf2,

0xf0,0xef,0xed,0xec,0xea,0xe8,0xe6,0xe4,0xe3,0xe1,0xde,0xdc,

0xda,0xd8,0xd6,0xd3,0xd1,0xce,0xcc,0xc9,0xc7,0xc4,0xc1,0xbf,

0xbc,0xb9,0xb6,0xb4,0xb1,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,

0x99,0x96,0x92,0x8f,0x8c,0x89,0x86,0x83,0x80,0x7d,0x79,0x76,

0x73,0x70,0x6d,0x6a,0x67,0x64,0x61,0x5e,0x5b,0x58,0x55,0x52,

0x4f,0x4c,0x49,0x46,0x43,0x41,0x3e,0x3b,0x39,0x36,0x33,0x31,

0x2e,0x2c,0x2a,0x27,0x25,0x23,0x21,0x1f,0x1d,0x1b,0x19,0x17,

0x15,0x14,0x12,0x10,0xf,0xd,0xc,0xb,0x9,0x8,0x7,0x6,0x5,0x4,

0x3,0x3,0x2,0x1,0x1,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,

0x0,0x1,0x1,0x2,0x3,0x3,0x4,0x5,0x6,0x7,0x8,0x9,0xa,0xc,0xd,

0xe,0x10,0x12,0x13,0x15,0x17,0x18,0x1a,0x1c,0x1e,0x20,0x23,

0x25,0x27,0x29,0x2c,0x2e,0x30,0x33,0x35,0x38,0x3b,0x3d,0x40,

0x43,0x46,0x48,0x4b,0x4e,0x51,0x54,0x57,0x5a,0x5d,0x60,0x63,

0x66,0x69,0x6c,0x6f,0x73,0x76,0x79,0x7c

}//用于生成正弦

unsigned char kscan() //键盘扫描函数

{

unsigned char kscannum,t

P1=0xff

t=P1

if(~(t&0xff))

{

if(k0==0)

{

kscannum=1

}

else if(k1==0)

{

kscannum=2

}

else if(k2==0)

{

kscannum=3

}

else if(k3==0)

{

kscannum=4

}

else if(k4==0)

{

kscannum=5

}

else

{

kscannum=0

}

return kscannum

}

}

void init_DA0832()//DA0832初始化

{

rd=0

wr=0

}

void fangbo()//产生方波函数

{

EA=1//开总中断

ET0=1//计时器T0工作

TMOD=1

TR0=1//开启T0

TH0=0xff//装入初值

TL0=0x83

}

void sin()//产生正弦波函数

{

unsigned inti

do{

P2=sin_code[i]

i=i+1

}while(i<256)

}

void juchibo()//产生锯齿波函数

{

P2=0x00

do{

P2=P2+1

}while(P2<=0xff)

}

void sanjiaobo()//产生三角波函数

{

P2=0x00

do{

P2=P2+1

}while(P2<0xff)

P2=0xff

do{

P2=P2-1

}while(P2>0x00)

P2=0x00

}

void tixingbo()//产生梯形波函数

{

unsigned char i

P2=0x00

do{

P2=P2+1

}while(P2<0xff)

P2=0xff

for(i=255i>0i--)

{

P2=0xff

}

do{

P2=P2-1

}while(P2>0x00)

P2=0x00

}

void timer0(void) interrupt 1//中断函数

{

P2=~P2//取反

TH0=0xff//重新装入初值

TL0=0x83

TR0=1

}

/*主函数*/

void main()

{

init_DA0832()//初始化

do

{

flag=kscan()

}while(!flag)//等待按键按下

while(1)

{

switch(flag)

{

case 1:

do{

flag=kscan()

sin()

}while(flag==1)//产生正弦波

break

case 2:

fangbo()

do{

flag=kscan()

}while(flag==2)//产生方波

TR0=0

break

case 3:

do{

flag=kscan()

sanjiaobo()

}while(flag==3)//产生三角波

break

case 4:

do{

flag=kscan()

tixingbo()

}while(flag==4)//产生梯形波

break

case 5:

do{

flag=kscan()

juchibo()

}while(flag==5)//产生锯齿波

break

default:

flag=kscan()

break

}

}

}

第一：div_7513count在分频的时候我看不出来它是几位，不知道你的时钟到底用的是多少。技术手册最低要求10M的配置时钟，太高不稳定。

第二：时而有输出时而没有，肯定是你的配置时序有问题。可以肯定不没有做过功能仿真。

第三：一般DAC的配置需求时序也不严格，只是你的配置时序太乱了！

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