Ex25_ZQ28335_IIR.zip_IIR DSP_iir

//########################################################################### // // 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: // IIR无限脉冲响应数字滤波器 数字信号处理 //########################################################################### #include "DSP28x_Project.h" // Device Headerfile and Examples Include File #include "math.h" #define IIRNUMBER 2 #define SIGNAL1F 1000 #define SIGNAL2F 4500 #define SAMPLEF 10000 #define PI 3.1415926 float InputWave(); float IIR(); float fBn[IIRNUMBER]={ 0.0,0.7757 }; float fAn[IIRNUMBER]={ 0.1122,0.1122 }; float fXn[IIRNUMBER]={ 0.0 }; float fYn[IIRNUMBER]={ 0.0 }; float fInput,fOutput; float fSignal1,fSignal2; float fStepSignal1,fStepSignal2; float f2PI; int i; float fIn[256],fOut[256]; int nIn,nOut; void main(void) { nIn=0; nOut=0; f2PI=2*PI; fSignal1=0.0; fSignal2=PI*0.1; // fStepSignal1=2*PI/30; // fStepSignal2=2*PI*1.4; fStepSignal1=2*PI/50; fStepSignal2=2*PI/2.5; // Step 1. Initialize System Control: // PLL, WatchDog, enable Peripheral Clocks // This example function is found in the DSP2833x_SysCtrl.c file. InitSysCtrl(); // 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(); // Step 4. for(;;) { fInput=InputWave(); fIn[nIn]=fInput; nIn++; nIn%=256; fOutput=IIR(); fOut[nOut]=fOutput; nOut++; if ( nOut>=256 ) { nOut=0; /* 请在此句上设置软件断点 */ } } } float InputWave() { for ( i=IIRNUMBER-1;i>0;i-- ) { fXn[i]=fXn[i-1]; fYn[i]=fYn[i-1]; } fXn[0]=sin(fSignal1)+cos(fSignal2)/6.0; fYn[0]=0.0; fSignal1+=fStepSignal1; if ( fSignal1>=f2PI ) fSignal1-=f2PI; fSignal2+=fStepSignal2; if ( fSignal2>=f2PI ) fSignal2-=f2PI; return(fXn[0]); } float IIR() { float fSum; fSum=0.0; for ( i=0;i<IIRNUMBER;i++ ) { fSum+=(fXn[i]*fAn[i]); fSum+=(fYn[i]*fBn[i]); } return(fSum); } //=========================================================================== // No more. //===========================================================================