ud23
Advanced Member level 3
hi i want to generate sine wave of 100khz using 89c52 with ad9833 i wrote code for it but its not working any one help me i am geting .31offset voltage at output of ad9833 here is my code....
#include <reg51.h>
sbit dds_en=P3^2; //it spi pin fsync or chip select
sbit dds_clk=P3^1; // it is input clk for ad9833
sbit dds_dat=P3^0; //ad9833 data pin
unsigned char control;
void delay(unsigned int i)
{
while(i)
{
i--;
}
}
void write_data(unsigned int a) //write 2 byte to dds
{
unsigned char i;
dds_clk=1; //set all control pin high for initalization
dds_dat=1;
dds_en=1;
control=0;
delay(1000);
dds_clk=1;
delay(2);
dds_en=0;
for(i=0;i<16;i++) //take 16 bit data to write
{
if(a&0x8000)
{
dds_dat=1;
}
else dds_dat=0;
dds_clk=0;
delay(5);
dds_clk=1;
a=a<<1;
}
delay(2);
dds_en=1;
dds_clk=0;
delay(1000);
control=1;
}
void init_dds(void)
{
write_data(0x2100); //to wite
write_data(0x2000); //reset ad9833
write_data(0x400B); //ferq0 reg msb value
write_data(0x4000); // ferq0 reg lsb value
write_data(0x800B);
write_data(0x8000);
write_data(0xC000); //phase0 reg
write_data(0xE000); // phase1 reg
write_data(0x2000); // reset ad9833
}
void output(unsigned long freq_value)
{
unsigned long dds;
unsigned int dds1,dds2;
dds=freq_value*10;//set output freuency0 reg equetion
dds=dds<<2; //shift that 2 bit
dds1=dds; //save that data
dds2=dds>>16; //shift dds value 16 data
dds1=dds1>>2; //take 2 controlbit
dds2=dds2&0x7FFF; //mask all bits
dds2=dds2|0x4000; //
dds1=dds1&0x7FFF;
dds1=dds1|0x4000;
write_data(0x2000);
write_data(dds1);
write_data(dds2);
}
void main()
{
//
init_dds();
output(1) ;
}
#include <reg51.h>
sbit dds_en=P3^2; //it spi pin fsync or chip select
sbit dds_clk=P3^1; // it is input clk for ad9833
sbit dds_dat=P3^0; //ad9833 data pin
unsigned char control;
void delay(unsigned int i)
{
while(i)
{
i--;
}
}
void write_data(unsigned int a) //write 2 byte to dds
{
unsigned char i;
dds_clk=1; //set all control pin high for initalization
dds_dat=1;
dds_en=1;
control=0;
delay(1000);
dds_clk=1;
delay(2);
dds_en=0;
for(i=0;i<16;i++) //take 16 bit data to write
{
if(a&0x8000)
{
dds_dat=1;
}
else dds_dat=0;
dds_clk=0;
delay(5);
dds_clk=1;
a=a<<1;
}
delay(2);
dds_en=1;
dds_clk=0;
delay(1000);
control=1;
}
void init_dds(void)
{
write_data(0x2100); //to wite
write_data(0x2000); //reset ad9833
write_data(0x400B); //ferq0 reg msb value
write_data(0x4000); // ferq0 reg lsb value
write_data(0x800B);
write_data(0x8000);
write_data(0xC000); //phase0 reg
write_data(0xE000); // phase1 reg
write_data(0x2000); // reset ad9833
}
void output(unsigned long freq_value)
{
unsigned long dds;
unsigned int dds1,dds2;
dds=freq_value*10;//set output freuency0 reg equetion
dds=dds<<2; //shift that 2 bit
dds1=dds; //save that data
dds2=dds>>16; //shift dds value 16 data
dds1=dds1>>2; //take 2 controlbit
dds2=dds2&0x7FFF; //mask all bits
dds2=dds2|0x4000; //
dds1=dds1&0x7FFF;
dds1=dds1|0x4000;
write_data(0x2000);
write_data(dds1);
write_data(dds2);
}
void main()
{
//
init_dds();
output(1) ;
}