agc_audio.c

在C54X DSP 下写的

#include "agc_inter.h"
#include "init_ad_bsp.h"


int		din,dout;

int		read_bsp(void);
void	write_bsp(int);

void	led_light(void);
int		agc_audio(int);

void	main()
{
	init_board;
	
	while(1)
	{
		din=read_bsp();
		dout=agc_audio(din);
		write_bsp(dout);
		led_light();
	}
}


int		read_bsp(void)
{
	int		datain;
	
	*(volatile u16 *)SPSA_ADDR(1)=SPCR1_SUBADDR;
	while(!((*(volatile u16 *)SPSD_ADDR(1)) & 0x0002))	{};
	datain=*(volatile u16 *)DRR1_ADDR(1);
	
	return	datain;
}

void	write_bsp(int dataout)
{
	*(volatile u16 *)SPSA_ADDR(1)=SPCR2_SUBADDR;
	while( !((*(volatile u16 *)SPSD_ADDR(1)) & 0x0002) )   {};
	*(volatile u16 *)DXR1_ADDR(1)=dataout;
}

void	led_light(void)
{
	static	int i=0;
	
	if(i>1024)
	{
		*(volatile u16 *)reg_ST1^=0x2000;
		i=0;
	}
	i++;
}




//AGC子函数
int		agc_audio(int agc_in)
{
	int		agc_out;		//输出变量,agc_in为输入变量
	
	static  int		dtime=0;
	static	float	agc_coff=0.0;
	static	int		maxagc_in=0;
	static	int		maxarrin=0;
	
	if(agc_in > maxarrin)
		maxarrin=agc_in;
		
	if(-1*agc_in > maxarrin)
		maxarrin=-1*agc_in;
		
	if(dtime >= 4096)
	{
		if(maxarrin < maxagc_in)
			maxagc_in=maxarrin;
		
		maxarrin=0;
		dtime=0;
	}
	dtime++;
	
	if(agc_in > maxagc_in)
	{
		maxagc_in=agc_in;
		if(maxagc_in > 1)
			agc_coff=20000.0/maxagc_in;
	}
	
	if((-1*agc_in)>maxagc_in)
	{
		maxagc_in=-1*agc_in;
		if(maxagc_in>1)
			agc_coff=20000.0/maxagc_in;
	}
	
	agc_out=agc_in*agc_coff;
	
	if(agc_out > 20000)
		agc_out=20000;
		
	if(agc_out< -20000)
		agc_out=-20000;
		
	return	agc_out;
	
	
	
	
	
	
}