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//###########################################################################
//
// FILE: Example_2833x_FFT.c
//
// TITLE: FFT
//
// ASSUMPTIONS:
//
// This program requires the DSP2833x header files.
//
// Two different examples are included. Select the example
// to execute before compiling using the #define statements
// found at the top of the code.
//
// As supplied, this project is configured for "boot to SARAM"
// operation. The 2833x Boot Mode table is shown below.
// For information on configuring the boot mode of an eZdsp,
// please refer to the documentation included with the eZdsp,
//
// $Boot_Table:
//
// GPIO87 GPIO86 GPIO85 GPIO84
// XA15 XA14 XA13 XA12
// PU PU PU PU
// ==========================================
// 1 1 1 1 Jump to Flash
// 1 1 1 0 SCI-A boot
// 1 1 0 1 SPI-A boot
// 1 1 0 0 I2C-A boot
// 1 0 1 1 eCAN-A boot
// 1 0 1 0 McBSP-A boot
// 1 0 0 1 Jump to XINTF x16
// 1 0 0 0 Jump to XINTF x32
// 0 1 1 1 Jump to OTP
// 0 1 1 0 Parallel GPIO I/O boot
// 0 1 0 1 Parallel XINTF boot
// 0 1 0 0 Jump to SARAM <- "boot to SARAM"
// 0 0 1 1 Branch to check boot mode
// 0 0 1 0 Boot to flash, bypass ADC cal
// 0 0 0 1 Boot to SARAM, bypass ADC cal
// 0 0 0 0 Boot to SCI-A, bypass ADC cal
// Boot_Table_End$
//
// DESCRIPTION:
// FFT变换 数字信号处理
//
//
//
//###########################################################################
// $TI Release: DSP2833x/DSP2823x Header Files V1.20 $
// $Release Date: August 1, 2008 $
//###########################################################################
#include "DSP28x_Project.h" // Device Headerfile and Examples Include File
#include"math.h"
#define PI 3.1415926
#define SAMPLENUMBER 512
Uint16 *ExRamStart = (Uint16 *)0x100000;
#define FIRNUMBER 25
int16 INPUT[SAMPLENUMBER];
// Prototype statements for functions found within this file.
void scib_echoback_init(void);
void scib_fifo_init(void);
void scib_xmit(int a);
void scib_msg(char *msg);
// Global counts used in this example
Uint16 LoopCount;
Uint16 ErrorCount;
int16 InputWave[SAMPLENUMBER];
void InitForFFT();
void FFT(float dataR[SAMPLENUMBER],float dataI[SAMPLENUMBER]);
void MakeWave();
//void FFT(float dataR[SAMPLENUMBER],float dataI[SAMPLENUMBER]);
//#pragma DATA_SECTION(INPUT, ".INPUT")
int INPUT[SAMPLENUMBER];
int DATA[SAMPLENUMBER];
int16 DATA2[SAMPLENUMBER];
//int INPUT[SAMPLENUMBER],DATA[SAMPLENUMBER];
float fWaveR[SAMPLENUMBER],fWaveI[SAMPLENUMBER],w[SAMPLENUMBER];
float sin_tab[SAMPLENUMBER],cos_tab[SAMPLENUMBER];
void MakeWave()
{
int i;
for ( i=0;i<SAMPLENUMBER;i++ )
{
INPUT[i]=sin(PI*2*i/SAMPLENUMBER*3)*1024;//+sin(PI*2*i/SAMPLENUMBER*8)*100+sin(PI*2*i/SAMPLENUMBER*60)*1024;// ---1024
}
}
void main(void)
{
int i;
Uint16 ReceivedChar[10];
Uint16 cnt;
Uint16 cntf;
int16 sendchar;
int n;
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the DSP2833x_SysCtrl.c file.
InitSysCtrl();
InitScibGpio();
// Step 2. Initalize GPIO:
// This example function is found in the DSP2833x_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
// InitGpio(); Skipped for this example
// Step 3. Clear all interrupts and initialize PIE vector table:
// Disable CPU interrupts
DINT;
// Initialize PIE control registers to their default state.
// The default state is all PIE interrupts disabled and flags
// are cleared.
// This function is found in the DSP2833x_PieCtrl.c file.
InitPieCtrl();
// Disable CPU interrupts and clear all CPU interrupt flags:
IER = 0x0000;
IFR = 0x0000;
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example. This is useful for debug purposes.
// The shell ISR routines are found in DSP2833x_DefaultIsr.c.
// This function is found in DSP2833x_PieVect.c.
InitPieVectTable();
//*ExRamStart=0x1111;
// Step 4.
LoopCount = 0;
ErrorCount = 0;
cnt=0;
cntf=0;
n=0;
// flag=0;
scib_fifo_init(); // Initialize the SCI FIFO
scib_echoback_init(); // Initalize SCI for
InitForFFT();
ScibRegs.SCIFFRX.bit.RXFFOVRCLR=1;
for(;;)
{
if(cnt==SAMPLENUMBER)
{ cntf=1;}
else
{ cntf=0; }
while(ScibRegs.SCIFFRX.bit.RXFFST !=1) { } // wait for XRDY =1 for empty state
sendchar= ScibRegs.SCIRXBUF.all;
if(cntf==1)
{ //MakeWave();
for ( i=0;i<SAMPLENUMBER;i++ )
{
fWaveR[i]=InputWave[i];//INPUT[i];//
fWaveI[i]=0.0f;
w[i]=0.0f;
}
FFT(fWaveR,fWaveI);
for ( i=0;i<SAMPLENUMBER;i++ )
{
DATA[i]=w[i];
// sendchar=DATA[i];
// scib_xmit( DATA[i]);
}
cnt=0;
for(i=0;i<SAMPLENUMBER;i++)
{ InputWave[i]=0;
//DATA[i]=0;
}
}
else
{
if(sendchar==0x002C)
{
if (ReceivedChar[0]==0x002D)
{
for(i=1;i<n;i++)
InputWave[cnt]+=((ReceivedChar[i]-48)*pow(10,n-i-1));
InputWave[cnt]=0x10000-InputWave[cnt];
}
else
{for(i=0;i<n;i++)
InputWave[cnt]+=((ReceivedChar[i]-48)*pow(10,n-i-1));
}
n=0;
for(i=0;i<10;i++)
{ ReceivedChar[i]=0;
}
cnt++;
}
else
{ReceivedChar[n]= sendchar;
n++;
}
}
scib_xmit(sendchar);
LoopCount++;
}
}
/////////////////////////////////////////////////////
void FFT(float dataR[SAMPLENUMBER],float dataI[SAMPLENUMBER])
{
int x0,x1,x2,x3,x4,x5,x6,x7,xx;
int i,j,k,b,r,m,L;
float TR,TI,temp;
/********** following code invert sequence ************/
/********** 实现倒序 ************/
for ( i=0;i<SAMPLENUMBER;i++ )
{ x7=SAMPLENUMBER;
x0=x1=x2=x3=x4=x5=x6=0;
x0=i&0x01;
x1=(i/2)&0x01;
x2=(i/4)&0x01;
x3=(i/8)&0x01;
x4=(i/16)&0x01;
x5=(i/32)&0x01;
x6=(i/64)&0x01;
xx=x0*x7/2+x1*x7/4+x2*x7/8+x3*x7/16+x4*x7/32+x5*x7/64+x6;
dataI[xx]=dataR[i];/*虚部此时暂时没用，暂时做缓存数组*/
}
for ( i=0;i<SAMPLENUMBER;i++ )
{
dataR[i]=dataI[i]; dataI[i]=0;
}
/**************计算*SAMPLENUMBER=2^(m)中的m******************/
m=0;
for (j=SAMPLENUMBER;j>1;j=j/2)
{m=m+1;}
//printf("%d\n",m);
/************** following code FFT *******************/
for ( L=1;L<=m;L++ )
{ /* for(1) */
b=1; i=L-1;
while ( i>0 )
{
b=b*2; i--;
} /* b= 2^(L-1) */
for ( j=0;j<=b-1;j++ ) /* for (2) */
{ r=1; i=m-L;
while ( i>0 ) /* r=2^(m-L)*j，用于计算Wr */
{r=r*2; i--;}
r=r*j;
for ( k=j;k<SAMPLENUMBER;k=k+2*b ) /* for (3) */
{
TR=dataR[k]; TI=dataI[k]; temp=dataR[k+b];
dataR[k]=dataR[k]+dataR[k+b]*cos_tab[r]+dataI[k+b]*sin_tab[r];
dataI[k]=dataI[k]-dataR[k+b]*sin_tab[r]+dataI[k+b]*cos_tab[r];
dataR[k+b]=TR-dataR[k+b]*cos_tab[r]-dataI[k+b]*sin_tab[r];
dataI[k+b]=TI+temp*sin_tab[r]-dataI[k+b]*cos_tab[r];
} /* END for (3) */
} /* END for (2) */
} /* END for (1) */
for ( i=0;i<SAMPLENUMBER/2;i++ )
{
w[i]=sqrt(dataR[i]*dataR[i]+dataI[i]*dataI[i]);
}
} /* END FFT */
void InitForFFT()
{
int i;
for ( i=0;i<SAMPLENUMBER;i++ )
{
sin_tab[i]=sin(PI*2*i/SAMPLENUMBER);
cos_tab[i]=cos(PI*2*i/SAMPLENUMBER);
}
}
////////////////////////////////////////////////////
void scib_echoback_init()
{
// Note: Clocks were turned on to the Scib peripheral
// in the InitSysCtrl() function
ScibRegs.SCICCR.all =0x0007; // 1 stop bit, No loopback
// No parity,8 char bits,
// async mode, idle-line protocol
ScibRegs.SCICTL1.all =0x0003; // enable TX, RX, internal SCICLK,
// Disable RX ERR, SLEEP, TXWAKE
ScibRegs.SCICTL2.all =0x0003;
ScibRegs.SCICTL2.bit.TXINTENA =1;
ScibRegs.SCICTL2.bit.RXBKINTENA =1;
#if (CPU_FRQ_150MHZ)
ScibRegs.SCIHBAUD =0x0001; // 9600 baud @LSPCLK = 37.5MHz.
ScibRegs.SCILBAUD =0x00E7;
#endif
#if (CPU_FRQ_100MHZ)
ScibRegs.SCIHBAUD =0x0001; // 9600 baud @LSPCLK = 20MHz.
ScibRegs.SCILBAUD =0x0044;
#endif
ScibRegs.SCICTL1.all =0x0023; // Relinquish SCI from Reset
}
// Transmit a character from the SCI
void scib_xmit(int a)
{
while (ScibRegs.SCIFFTX.bit.TXFFST != 0) {}
ScibRegs.SCITXBUF=a;
}
void scib_msg(char * msg)
{
int i;
i = 0;
while(msg[i] != '\0')
{
scib_xmit(msg[i]);
i++;
}
}
// Initalize the SCI FIFO
void scib_fifo_init()
{
ScibRegs.SCIFFTX.all=0xE040;
ScibRegs.SCIFFRX.all=0x204f;
ScibRegs.SCIFFCT.all=0x0;
}
//===========================================================================
// No more.
//===========================================================================
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