實(shí)驗(yàn)四FIR濾波器實(shí)驗(yàn)

實(shí)驗(yàn)四FIR濾波實(shí)驗(yàn)一、實(shí)內(nèi)容1、掌握TMS320C54xDSPLIB函庫(kù)中函數(shù)的使用方法。2、學(xué)習(xí)并掌握5402DSP片外DMA的結(jié)構(gòu)與配置3、使用DMA數(shù)據(jù)傳輸方式在C語(yǔ)言下實(shí)現(xiàn)直接型的濾波器。二、實(shí)內(nèi)容、使查方設(shè)一低通波器通頻為2400HzFpass=2400,fstop=3000,fs=16000<type.h><board.h><tms320.h>voidperiod);hHandset;

s16/*sectionfor*/DATA_SECTION(coeffs,"coefficients");/*LowPassFilter*/coeffs[16]={985,-906,-2112,-1653,2005,10556,10556,2005,-1653,-906,985,2810};DATA_SECTION(delaybuff,"delay");delaybuff[16]={0};*delayptr=&(delaybuff[0]);out_buffer[1];*inp_ptr=inp_buffer;*out_ptr=out_buffer;void{s16cnt=2;if(brd_init(100))return;/*blinkledstimes*/cnt--){/*brd_delay_msec(1000);*/delay(1000);/*brd_delay_msec(1000);*/delay(1000);/*brd_delay_msec(1000);*/delay(1000);}/*Handset*/hHandset=/*Acquire*//*codecparameters*/codec_dac_mode(hHandset,CODEC_DAC_15BIT);/*DACmode*/codec_adc_mode(hHandset,CODEC_ADC_15BIT);/*ADCmode*/codec_ain_gain(hHandset,CODEC_AIN_6dB);/*gainontoADC*//*onDAC*/codec_sample_rate(hHandset,SR_16000);/*16KHzsamplingrate*//*digitalloopback*/{/*Waitfor*/

(!MCBSP_RRDY(HANDSET_CODEC)){};/*Readfromandcodec*/inp_buffer[0]=*(volatile/*據(jù)處理開(kāi)始*///fir計(jì)算fir(inp_ptr,coeffs,out_ptr,&delayptr,16,1);data=out_buffer[0]&0xfffe;/*據(jù)處理結(jié)束*/*(volatile=data;}}voidperiod){inti,j;for(i=0;i++){for(j=0;j++);}}2.使方式計(jì)FIR低濾器通截為4000Hz從5402DSK板MIC端口輸頻為3000Hz和5000Hz正弦號(hào)疊信，用波在端觀輸信波。Fpass=4000,fstop=5000,fs=16000<type.h><board.h><firlab.h>

voidperiod);externvoidhHandset;unsignedintunsignedintdmpre,dmidx1,dmfri0,dmfri1,dmgsa,/*sectionforbuffer(symbol,section_name)*/DATA_SECTION(buffer,"audio_buffer");int/*sectionfor*/DATA_SECTION(coeffs,"coefficients");/*LowPassFilter*/intcoeffs[16]={-1842,-686,-282,-3838,1948,-1842,};intdelaybuff[16]={0};/*declareandtwoforDMAC*/intintinttemp;intcurrbuff/*holdsaddressofstartofthebuffer*/int*delayptr1=&(delaybuff[0]);void{s16cnt=1;/*itemsthatBIOSwillwhenweuseit*/BSCR=0x8806;XPC=PMST=0xA0;TIMER_HALT(0);9);return;/*Handset*/

hHandsetcodec_open(HANDSET_CODEC);codec*//*codecparameters*/

/*Acquire

codec_dac_mode(hHandset,CODEC_DAC_15BIT);/*DACinmode*/codec_adc_mode(hHandset,CODEC_ADC_15BIT);/*ADCinmode*/codec_ain_gain(hHandset,CODEC_AIN_6dB);/*6dBgaininputtoADC*//*onoutputDAC*/codec_sample_rate(hHandset,SR_16000);/**//*ClearIFR*/INTR_CLR_FLAG(DMAC2);/*allDMA*/dma_reset_all();/*InitializeDMAchannel*/dmsefc=((DSYNC_REVT1=((AUTOINIT_ENABLE<<15)|(DINM_ENABLE14)||<<12)|(INDEXMODE_NOMOD<<8)|(SPACE_DATA|dmctr=src_addr=dst_addr=int)&buffer;SPACE_DATA,src_addr,SPACE_DATA,dst_addr);/*forchannel2*/DMA_FRAMECOUNT(DMA_CH2,2);/*upautoinitforDMACH2Input*/dmgsa=src_addr;dmgdadmgcr=dmgfr=/*uppriorityenablecontrolregister*/=((HIGH_PRIORITY|<<6));dmsrcp=SPACE_DATA;dmdstp=SPACE_DATA;==dmfri0dmfri1dma_global_init(dmpre,dmidx0,dmidx1,dmgda,dmgfr);/**//*primeserialbegininputbufferstream*/

*(volatile/*DMAC2interrupt*/INTR_ENABLE(DMAC2);/*GlobalInterrupts*//*EndlesswaitingforDMAC2interrupt*/for(;;);}voidperiod){inti,j;for(i=0;i++){for(j=0;j++);}}三、思題1、濾波器設(shè)計(jì)中為什么要設(shè)有遲緩沖存儲(chǔ)器delaybuff？其大小有什么限制？答在連續(xù)的數(shù)據(jù)塊計(jì)算時(shí)延遲緩沖區(qū)保存著后一次計(jì)算所要的前一次的輸出數(shù)據(jù)個(gè)緩沖存儲(chǔ)區(qū)的起點(diǎn)必須位于Kbit的界處始地址的最低K=log2nh個(gè)有位必須為零。2、使查詢(xún)方式和DMA中斷方設(shè)計(jì)濾波器時(shí)許DSP用數(shù)字信號(hào)處理程序的最大時(shí)間分別是多少？答詢(xún)方式允許DSP用于數(shù)字信號(hào)處理程序的最大時(shí)間是Ts,而DMA斷方式設(shè)計(jì)FIR波器時(shí)允許用于數(shù)字信號(hào)處理程序的最大時(shí)間是256Ts3、如設(shè)置CCS將濾波結(jié)果保存在外部數(shù)據(jù)文*.dat中？答采用文件的方式，使探測(cè)點(diǎn)與輸出文*.dat相關(guān)聯(lián)4、在察輸出信號(hào)頻譜波形時(shí)，為什么經(jīng)常發(fā)