firlab.c

DSP C5402 下的DMA滤波程序利用2通道输入

/*****************************************************************************/
/* FIRlab.C  AIC,McBSP,DMA initialization for FIR lab Filter                 */ 
/*                                                                           */
/* Goal:  This code performs the following functions:                        */
/*			- toggle the three LEDs on the DSK								 */
/*			- setup AIC (CODEC) parameters									 */
/*  		- initialize DMA Channel (CH2-input)			                 */
/*			- turn on interrupts											 */
/*			- run forever (waiting for DMA interrupts to transfer data)		 */
/*																			 */
/* Author: Scott Bland     Date: 03/20/2000									 */
/*****************************************************************************/
   
/*****************************************************************************/
/* Include Files                                                             */
/*****************************************************************************/

#include <type.h>
#include <board.h>
#include <codec.h>
#include <firlab.h>
#include <string.h>

/*****************************************************************************/
/* Function Prototypes                                                       */
/*****************************************************************************/

void delay(s16 period);
extern void DMAC2ISR();


/*****************************************************************************/
/* Global Variables                                                          */
/*****************************************************************************/

HANDLE hHandset;
unsigned int dmsefc, dmmcr, dmctr, src_addr, dst_addr;
unsigned int dmpre, dmsrcp, dmdstp, dmidx0, dmidx1, dmfri0, dmfri1, dmgsa, dmgda, dmgcr, dmgfr;

/* Create specific data section for buffer (symbol, section_name) */
#pragma DATA_SECTION(inp_buffer,"audio_buffer");
int inp_buffer[0x200];

/* Create specific data section for buffer (symbol, section_name) */
#pragma DATA_SECTION(out_buffer,"outt_buffer");
int out_buffer[0x200];


/* Create specific data section for coeffiecients */
#pragma DATA_SECTION(coeffs,"coefficients");
/* Low  Pass Filter fs=16000 fc=4000Hz*/ 
   int coeffs[16]={ -2, -30,127,372,-891,  -1925,   4228,  14507,14507,4228,-1925,-891,372,127, -30,-2};
/* High Pass Filter */ 
// int coeffs[16]={-120,5245,-3421,2451,-11216,40,-24657,29610,29610,-24657,40,-11216,2451,-3421,5245,-120}; 
/* Band Pass Filter */ 
/* int coeffs[16]={921,-2494,137,-3654,-2485,-2063,-9015,16165,16165,-9015,-2063,-2485,-3654,137,-2494,921};  */
/* Band Stop Filter */
/* int coeffs[16]={491,165,-2159,772,-6697,10044,648,12297,12297,648,10044,-6697,772,-2159,165,491}; */ 
/* All  Pass Filter */
/* int coeffs[16] ={32767,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};  */

/* Create specific data section for delay buffer  */
#pragma DATA_SECTION(delaybuff,"delayb");
int delaybuff[16]={0}; 
 

/* declare and initialize two variables for DMAC ISRs */

int frame=0; 
int flag=0;
int temp;   
int currbuff = 0;


/* delayptr holds the address of the start of the delay buffer */
     
int *delayptr1 = &(delaybuff[0]); 

interrupt void DMAC2ISR();


/*****************************************************************************/
/* MAIN                                                                      */
/*****************************************************************************/

void main()
{   
	s16 cnt=2;
	
/* These are the items that BIOS will set when we use it */

    BSCR = 0x8806;
    XPC = 0;
    PMST = 0xA0;
    brd_set_cpu_freq(100);
    TIMER_HALT(0); 
    brd_set_wait_states(7, 7, 9);
    TIMER_RESET(0); 
    IMR=0;		//禁止所有中断
/* ----------------------------------------------------- */

		if(brd_init_bios())	  			
        return;

   

while(cnt--)
	{
		brd_led_toggle(BRD_LED0);		//切换LED指示灯0的显示状态
		delay(1000);
		brd_led_toggle(BRD_LED1);		//切换LED指示灯1的显示状态
		delay(1000);
		brd_led_toggle(BRD_LED2);		//切换LED指示灯2的显示状态
		delay(1000);
	} 
         


/* Open Handset Codec */

    hHandset = codec_open(HANDSET_CODEC);               /* Acquire handle to codec */

/* Set codec parameters */

    codec_dac_mode(hHandset, CODEC_DAC_15BIT);          /* DAC in 15-bit mode */
    codec_adc_mode(hHandset, CODEC_ADC_15BIT);          /* ADC in 15-bit mode */
    codec_ain_gain(hHandset, CODEC_AIN_6dB);            /* 6dB gain on analog input to ADC */
    codec_aout_gain(hHandset, CODEC_AOUT_MINUS_6dB);    /* -6dB gain on analog output from DAC */
    codec_sample_rate(hHandset,SR_16000);               /* 16KHz sampling rate */

/* Clear IFR */
 
   INTR_CLR_FLAG(DMAC2);

/* Reset all DMA channels */ 

    dma_reset_all();


/* Initialize DMA channel 2 */

    dmsefc = ((DSYNC_REVT1 <<12));//DMA与McBSP1接收事件同步
    dmmcr = ((AUTOINIT_ENABLE << 15) | (DINM_ENABLE << 14) | (IMOD_HALFBLOCK <<13) | (CTMOD_DEC <<12) | (INDEXMODE_NOMOD << 8) | (SPACE_DATA << 6) | (INDEXMODE_INC << 2) | (SPACE_DATA));
//设置传输控制模式寄存器DMMCR
//15bit  AUTOINIT_ENABLE=1        使能自动初始化
//14bit  DINM_ENABLE=1            根据IMOD位产生中断
//13bit  IMOD_HALFBLOCK=1         帧和块结束时都产生中断
//12bit  CTMOD_DEC=0              减量计数模式(多帧模式)
//10-8bit   INDEXMODE_NOMOD=000   源地址模式No modify 
//7-6bit   SPACE_DATA=01          源地址空间为数据空间
//4-2bit   INDEXMODE_INC=01       目的地址模式, 传输之后加1
//1-0bit   SPACE_DATA=01          目的地址空间为数据空间
    
    dmctr = 0xFF;//单元记数,期望传输数据减