Vivado FFT IP核使用

1. 今日摸鱼任务

学习Vivado FFT IP核的使用

Vivado_FFT IP核使用详解_vivado fft ip核-CSDN博客

这篇写的很详细啦

简单做一点笔记进行记录

2. FFT IP核

xfft_0 ff (.aclk(aclk),                                                // input wire aclk.aresetn(aresetn),                                          // input wire aresetn.s_axis_config_tdata(s_axis_config_tdata),                  // input wire [23 : 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(s_axis_data_tlast),                      // 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(m_axis_data_tuser),                      // 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
);

看起来有这么多端口，貌似很麻烦捏：

AXI4-Stream这里重点是TVALID和TREADY：分清输入输出的主、从

3. matlab 程序

clc;clear;close all;
fs = 1e4;f1 = 5e2;
N = 1024;
t = 0:1/fs:(N-1)/fs;
x = sin(2*pi*f1*t)  ;
x = mapminmax(x).* (2^15-1);
fid = fopen('fft_test_signal.txt', 'wt');
for i = 1:Nif (x(i) >= 0)fprintf(fid, '%s\n', dec2bin(x(i),16));else fprintf(fid, '%s\n', dec2bin(2^16 + x(i), 16));end
end
fclose(fid);
y = fft(x(1:1024)) / 2^12;%缩放倍数在s_axis_config_tdata处
y_re = real(y);
y_im = imag(y);
figure(1);
subplot(3,1,1);plot(0:N-1,x);title('x = sin(2*pi*500*t)  fs = 10kHz');
subplot(3,1,2);plot(0:N-1,y_re);title('y re');
subplot(3,1,3);plot(0:N-1,y_im);title('y im');

4. FFT 配置与验证

`timescale 1ns / 1ns
module fft_tb(    );reg aclk;reg aresetn;reg [23:0] s_axis_config_tdata;reg s_axis_config_tvalid;reg [31:0] s_axis_data_tdata;reg s_axis_data_tvalid;reg s_axis_data_tlast;reg m_axis_data_tready;wire [31:0] m_axis_data_tdata;wire [9:0] m_axis_data_tuser;wire m_axis_data_tlast;wire m_axis_data_tvalid;wire s_axis_config_tready;wire s_axis_data_tready;wire event_frame_started;wire event_tlast_unexpectedl;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;reg [15:0] data_in[0:1024-1];integer i;wire [15:0] Xk_Re, Xk_Im;assign Xk_Re = m_axis_data_tdata[31:16];assign Xk_Im = ~m_axis_data_tdata[15:0]+1'b1;//取反initial aclk = 1'b1;always#10aclk = ~aclk ;initialbegin$readmemb("E:/vivado/fft/fft_test_signal.txt", data_in);aresetn = 1'b0;s_axis_config_tdata = {7'b000_0000, 16'b_01_01_10_01_10_10_01_10, 1'b1};//s缩放倍数 1+1+2+1+2+2+1+2=12  2的12次幂对应matlabs_axis_config_tvalid = 1'b1;i = 0;s_axis_data_tdata = 32'd0;s_axis_data_tlast = 1'b0;m_axis_data_tready = 1'b1;# 40;aresetn = 1'b1;  forever begin@(negedge aclk) if(s_axis_data_tready == 1'b1) begins_axis_data_tvalid = 1'b1;s_axis_data_tdata = {data_in[i], 16'd0};if(i == 1024-1) i = 0;else i = i+1;endelse s_axis_data_tvalid = 1'b0;      end$stop;  endxfft_0 ff (.aclk(aclk),                                                // input wire aclk.aresetn(aresetn),                                          // input wire aresetn.s_axis_config_tdata(s_axis_config_tdata),                  // input wire [23 : 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(s_axis_data_tlast),                      // 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(m_axis_data_tuser),                      // output wire [9: 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

这个取补码可以正数变负数、负数变正数（这个小问题下周推导一下）