在做32点fft vivado实现时，对比matlab结果，发现对不上，是我代码有问题吗
IP核配置
俩出来的结果
matlab 代码
Fs = 1e9 ;
t = 0:1/Fs:31/Fs ;
length = 32 ;
n = 1:length ;
f1 = 31.25e6 ;
f2 = 300e6 ;
s1 = cos(2*pi*f1*t) ;
s2 = cos(2*pi*f2*t) ;
signalN = s1 + s2 ;
data_before_fft = 100* signalN ; %系数放大100倍
figure;hold on ;
plot(n, s1) ;
plot(n, s2) ;
hold off ;
figure;plot(n(1:32), signalN(1:32)) ;
title('输入信号') ;
fp = fopen('data_before_fft.txt','w') ;
for i = 1:length
if(data_before_fft(i)>=0)
temp = dec2bin(data_before_fft(i),16) ;
else
temp = dec2bin(data_before_fft(i)+2^16+1,16) ;
end
% temp = s_bin(i,:);
for j = 1:16
fprintf(fp,'%s',temp(j)) ;
end
fprintf(fp,'\r\n') ;
end
fclose(fp) ;
data_after_fft1 = fft(data_before_fft) ;
data_after_fft = data_after_fft1.' ;
data_real = real(data_after_fft) ;
data_imag = imag(data_after_fft) ;
data_r_i = [data_real, data_imag];
vivado 代码
module fft(
input wire clk,
input wire [15:0] din,
input wire last,
input wire s_axis_data_tvalid,
output wire [15:0] m_axis_data_tdata_r,
output wire [15:0] m_axis_data_tdata_i,
output wire [7:0] index
);
wire [31:0]s_axis_data_tdata;
wire [7:0]s_axis_config_tdata = {7'b0,1'b1};//NO need run time change length!
wire s_axis_config_tvalid = 1;
wire s_axis_config_tready ;
wire s_axis_data_tready ;
//wire s_axis_data_tlast = 0;
//wire s_axis_data_tvalid = 1 ;
//wire [7:0] index;
wire m_axis_data_tvalid;
wire m_axis_data_tready = 1;
wire m_axis_data_tlast=0;
wire event_frame_started;
wire event_tlast_unexpected;
wire event_tlast_missing;
wire event_status_channel_halt;
wire event_data_in_channel_halt;
wire event_data_out_channel_halt;
wire [31:0] m_axis_data_tdata;
assign s_axis_data_tdata = {16'b0,din};
assign m_axis_data_tdata_r = m_axis_data_tdata[15:0];
assign m_axis_data_tdata_i = m_axis_data_tdata[31:16];
xfft_0 fft_test (
.aclk(clk), // input wire aclk
.s_axis_config_tdata(s_axis_config_tdata), // input wire [7 : 0] s_axis_config_tdata
.s_axis_config_tvalid(s_axis_config_tvalid), // input wire s_axis_config_tvalid
.s_axis_config_tready(s_axis_config_tready), // output wire s_axis_config_tready
.s_axis_data_tdata(s_axis_data_tdata), // input wire [31 : 0] s_axis_data_tdata
.s_axis_data_tvalid(s_axis_data_tvalid), // input wire s_axis_data_tvalid
.s_axis_data_tready(s_axis_data_tready), // output wire s_axis_data_tready
.s_axis_data_tlast(last), // input wire s_axis_data_tlast
.m_axis_data_tdata(m_axis_data_tdata), // output wire [31 : 0] m_axis_data_tdata
.m_axis_data_tuser(index), // output wire [7 : 0] m_axis_data_tuser
.m_axis_data_tvalid(m_axis_data_tvalid), // output wire m_axis_data_tvalid
.m_axis_data_tready(m_axis_data_tready), // input wire m_axis_data_tready
.m_axis_data_tlast(m_axis_data_tlast), // output wire m_axis_data_tlast
.event_frame_started(event_frame_started), // output wire event_frame_started
.event_tlast_unexpected(event_tlast_unexpected), // output wire event_tlast_unexpected
.event_tlast_missing(event_tlast_missing), // output wire event_tlast_missing
.event_status_channel_halt(event_status_channel_halt), // output wire event_status_channel_halt
.event_data_in_channel_halt(event_data_in_channel_halt), // output wire event_data_in_channel_halt
.event_data_out_channel_halt(event_data_out_channel_halt) // output wire event_data_out_channel_halt
);
endmodule
tb
module tb_fft();
reg clk;
reg [15:0] din;
reg [15:0] stimulus[1:32];//32位
integer count;
integer i;
integer file;
wire [15:0] data_real;
wire [15:0] data_imag;
wire [7:0] index;
reg last;
reg s_axis_data_tvalid;
initial begin
clk = 0;
din = 0;
count = 0;
last = 0;
s_axis_data_tvalid = 0;
#10;
$readmemb("C:/Users/hp/OneDrive/桌面/FFT/data_before_fft.txt", stimulus);
file = $fopen("C:/Users/hp/OneDrive/桌面/FFT/data_before_fft.txt", "w");
#10;
for(i = 1;i<=32;i = i+1)begin
s_axis_data_tvalid = 1;
din = stimulus[i];
#4;
end
last = 1;
s_axis_data_tvalid = 0;
din = 16'b0;
end
always # 2 clk = ~clk;
always @(posedge clk) begin
$fwrite(file,"%h\n", data_real); //data_o为需要保存的信号数据
if(count > 2500)
$fclose(file);
count = count + 1;
end
fft fft_test(
.clk(clk),
.din(din),
.last(last),
.s_axis_data_tvalid(s_axis_data_tvalid),
.m_axis_data_tdata_r(data_real),
.m_axis_data_tdata_i(data_imag),
.index(index)
);
endmodule
