qut_filt_plot.m

FPGA开发光盘各章节实例的设计工程与源码

%------------------算法的 Quartus 仿真结果------------------%
%           f1=150;                                                             %
%           f2=330;                                                             %
%           fs=1000;                                                           %
%           fir_coef=0.5;                                                     %
%           i=3.1415926;                                                    %    
%           dets=1/fs;                                                         %
%           fp=fir_coef*fs/2;                                                %    
%-------------------------------------------------------------------%
%-----------------读入的数据总数是158个--------------------%
%-------------------------------------------------------------------%

disp('%--------滤波算法的 Quartus 仿真结果--------%');

indata_plot;
 
fs=1000;
dets=1/fs;
fid=fopen('..\matlab\filter.tbl','r');
k=0;
 %for i=1:530 %-- i 的取值与要读入的数据总数有关。每多一个点，则循环次数加2。
    A1='1';
    A1_next='0';
 while A1_next~='X'
    A1_next=fscanf(fid,'%s',1);
    if (A1_next=='0')
        A1='0';
        A1_next=fscanf(fid,'%s',1);
    end;
    if(A1=='0')
        A1_next=fscanf(fid,'%s',1);
        A1_next=fscanf(fid,'%s',1);
        A1_next=fscanf(fid,'%s',1);
      if(A1_next=='1') 
        A1='1';
        A1_next=fscanf(fid,'%s',1);  %取出‘＝’
        A1_next=fscanf(fid,'%s',1);
        data=A1_next;
        k=k+1;
        wauk_bin=dec2bin(hex2dec(data),18);
        %wauk_hao(k)=0;
        if (wauk_bin(1)==dec2bin(1))
          for j=1:18
            if wauk_bin(j)==dec2bin(1)
               wauk_bin(j)=dec2bin(0);
            else
                wauk_bin(j)=dec2bin(1);
            end;
          end;
          wauk_hao(k)=-(bin2dec(wauk_bin)+1);
        else
          wauk_hao(k)=hex2dec(data);
        end;
      end;
    end;
 end;
 fclose(fid);
 
 subplot(2,2,3);
 plot([0:k-1]*dets,wauk_hao*2/32767,'-m');
 axis([0.006,0.1,-2,2]);
 title ('Quartus的输出数据时域','fontsize',8);
 xlabel ('时间t（秒）','fontsize',8);
 ylabel ('幅度y','fontsize',8);

 subplot(2,2,4);
 stem(abs(fft(wauk_hao*2/32767)),'*m');
 axis([0,80,0,80]);
 title ('Quartus的输出数据频域','fontsize',8);
 xlabel ('频率（赫兹）','fontsize',8');
 ylabel ('幅度Y','fontsize',8);