Zynq—AD9238数据采集DDR3缓存千兆以太网发送实验(前导)
Zynq—AD9238数据采集DDR3缓存千兆以太网发送实验(一)
五、实验目的
本次实验使用电脑上的网络调试助手,将命令帧通过以太网芯片RTL8211(RGMII接口)发送至ACZ7015开发板,提取UDP报文内容转换成控制命令,从而实现对ACM9238模块采样频率、数据采样个数以及采样通道的配置。
配置完成之后,ACM9238模块开始采集数据,将采集的数据存储至DDR3中,然后通过网口以UDP协议传输到电脑。用户可以在电脑上通过网口调试工具进行指令的下发,并以文件的形式保存接收到的数据,然后使用MATLAB软件进行进一步的数据处理分析。
PL 部分的模块说明如下:
- pll 模块: 锁相环模块, 输入时钟 50M, 由 PS 输出给 PL; 输出 100M 的时钟给到 DDR3 控制器使用; 输出 50M 的时钟给其它模块使用。
- eth_receive_cmd 模块: 以太网接收命令模块, 对以太网接收到的数据进行分析, 将接收的数据转换成相应的控制数据并输出到对应的模块。
- ad9238_ctrl 模块: ACM9238 控制器模块, 该模块内部包含速度控制模块,以及数据位宽转换模块。
- state_ctrl 模块: ADC 采集数据 DDR3 缓存以太网发送状态控制模块, 协调各个模块的信号控制, 程序状态的总控制模块。
- fifo_axi4_adapter 模块: fifo 接口到 AXI4 接口的转换模块(含 2 个 FIFO)。
六、ACM9238模块
两路,
采样上限50Msps,如果期望以1Msps 的采样速率采样, 则只需要每间隔 50 个采样数据取一个结果存储或使用, 其他 49 个数据直接舍弃。不建议降低ADC芯片的时钟信号。
七、设计实例
7.1模块设计
7.1.1 eth_receive_cmd模块
将以太网接收到的数据进行解析, 得到控制命令。
(1)eth_udp_rx_gmii模块和rgmii_to_gmii模块
(2)mmcm模块
锁相环模块,将 rgmii 接口时钟信号 rgmii_rx_clk_i 偏移90 °得到 rgmii_rx_clk 时钟信号。(为了在时钟信号的上升沿/下降沿取数据时,取得数据刚好是数据信号 rgmii_rxd 的正中间, 使得采样的数据处于最稳定的状态。)
锁相环IP配置
(3)fifo_rx模块
使用该 IP 核解决采集过程中会出现的跨时钟域数据交互问题(以太网125MHz,ACM9238-50MHz)。
(4)eth_cmd模块
接收转命令模块。
//非空时产生FIFO读请求信号
always@(posedge clk or negedge reset_n)
if(!reset_n)
fifo_rd_req <= 1'b0;
else if(!rx_empty)
fifo_rd_req <= 1'b1;
else
fifo_rd_req <= 1'b0;
//获得帧命令数据
always@(posedge clk)
if(fifo_rd_req)begin
data_0[7] <= #1 fifodout;
data_0[6] <= #1 data_0[7];
data_0[5] <= #1 data_0[6];
data_0[4] <= #1 data_0[5];
data_0[3] <= #1 data_0[4];
data_0[2] <= #1 data_0[3];
data_0[1] <= #1 data_0[2];
data_0[0] <= #1 data_0[1];
end
//判断帧命令数据
always@(posedge clk or negedge reset_n)
if(!reset_n)begin
address <= 0;
cmd_data <= 32'd0;
cmdvalid <= 1'b0;
end
else if(fifo_rx_done)begin
if((data_0[0]==8'h55)&&(data_0[1]==8'hA5)&&(data_0[7]==8'hF0))
begin
cmd_data[7:0] <= #1 data_0[6];
cmd_data[15:8] <= #1 data_0[5];
cmd_data[23:16] <= #1 data_0[4];
cmd_data[31:24] <= #1 data_0[3];
address <= #1 data_0[2];
cmdvalid <= #1 1;
end
else
cmdvalid <= #1 0;
end
else
cmdvalid <= #1 0;
(5)cmd_rx模块
接收数据转换为控制数据。
寄存器说明:
always@(posedge clk or negedge reset_n)
if(!reset_n)begin
ChannelSel <= 2'b00;
DataNum <= 32'd0;
ADC_Speed_Set <= 32'd0;
RestartReq <= 1'b0;
end
else if(cmdvalid)begin
case(cmd_addr)
0: RestartReq <= 1'b1;
1: ChannelSel <= cmd_data[1:0];
2: DataNum <= cmd_data[31:0];
3: ADC_Speed_Set <= cmd_data[31:0];
default:;
endcase
end
else
RestartReq <= 1'b0;
7.1.2 ad9238_ctrl 模块
控制ADC的采样速率,将12位数据转换为16位数据。
(1)speed_ctrl模块
always@(posedge clk or negedge reset_n)
if(!reset_n)
div_cnt <= 0;
else if(ad_sample_en)begin
if(div_cnt >= div_set)
div_cnt <= 0;
else
div_cnt <= div_cnt + 1'd1;
end
else
div_cnt <= 0;
always@(posedge clk or negedge reset_n)
if(!reset_n)
adc_data_en <= 0;
else if(div_cnt == div_set)
adc_data_en <= 1;
else
adc_data_en <= 0;
(2)ad_12bit_to_16bit模块
always @(posedge clk)
ad_out_valid <= ad_sample_en;
assign s_ad_in1 = ad_in1 + 12'd2048;
assign s_ad_in2 = ad_in2 + 12'd2048;
always @(posedge clk)
if(ad_sample_en && ch_sel == 2'b01)
ad_out<={4'd0,s_ad_in1};//这样补 0 为了适应上位机
else if(ad_sample_en && ch_sel == 2'b10)
ad_out<={4'd0,s_ad_in2};//
else if(ad_sample_en && ch_sel == 2'b00)
ad_out<={4'd0,adc_test_data};
else
ad_out <= 16'd0;
7.1.3 state_ctrl 模块
控制信号的产生以及 ADC 何时启动数据传输。
localparam IDLE = 4'd0; //空闲状态
localparam DDR_WR_FIFO_CLEAR = 4'd1; //DDR 写 FIFO 清除状态
localparam ADC_SAMPLE = 4'd2; //ADC 采样数据状态
localparam DDR_RD_FIFO_CLEAR = 4'd3; //DDR 读 FIFO 清除状态
localparam DATA_SEND_START = 4'd4; //数据发送状态
localparam DATA_SEND_WORKING = 4'd5; //数据发送完成状态
(1)IDLE
//ADC 模块开始采样标志信号寄存
always@(posedge clk or posedge reset)begin
if(reset)
start_sample_rm <= 1'b0;
else if(state==IDLE)
start_sample_rm <= start_sample;
else
start_sample_rm <= 1'b0;
end
/*状态切换IDLE->DDR_WR_FIFO_CLEAR
begin
if(start_sample_rm) begin //DDR 初始化完成并且产生启动采样信号
state <= DDR_WR_FIFO_CLEAR; //进入写 FIFO 清除状态
end
else begin
state <= state;
end
end
*/
(2)DDR_WR_FIFO_CLEAR
//延时10个节拍
always@(posedge clk or posedge reset)begin
if(reset)
wrfifo_clr_cnt<=0;
else if(state==DDR_WR_FIFO_CLEAR)//如果进入了清 fifo 状态
begin
if(wrfifo_clr_cnt==9)
wrfifo_clr_cnt<=5'd9;
else
wrfifo_clr_cnt<=wrfifo_clr_cnt+1'b1;
end
else
wrfifo_clr_cnt<=5'd0;
end
//给清FIFO信号足够的拉高时间
always@(posedge clk or posedge reset)begin
if (reset)
wrfifo_clr<=0;
else if(state==DDR_WR_FIFO_CLEAR)
begin
if(wrfifo_clr_cnt==0||wrfifo_clr_cnt==1||wrfifo_clr_cnt==2)
wrfifo_clr<=1'b1;
else
wrfifo_clr<=1'b0;
end
else
wrfifo_clr<=1'b0;
end
/*状态切换DDR_WR_FIFO_CLEAR->ADC_SAMPLE
begin
if(!wrfifo_full && (wrfifo_clr_cnt==9))
state<=ADC_SAMPLE;
else
state<=DDR_WR_FIFO_CLEAR;
end
*/
(3)ADC_SAMPLE
//根据ADC输出使能信号计数
always@(posedge clk or posedge reset)begin
if(reset)
adc_sample_cnt<=1'b0;
else if(state==ADC_SAMPLE)begin
if(adc_data_en)
adc_sample_cnt<=adc_sample_cnt+1'b1;
else
adc_sample_cnt<=adc_sample_cnt;
end
else
adc_sample_cnt<=1'b0;
end
//产生采样使能信号给其他模块
always@(posedge clk or posedge reset)begin
if(reset)
ad_sample_en<=0;
else if(state==ADC_SAMPLE)
ad_sample_en<=1;
else
ad_sample_en<=0;
end
/*状态切换ADC_SAMPLE->DDR_RD_FIFO_CLEAR
begin
if((adc_sample_cnt>=set_sample_num-1'b1)&& adc_data_en)
state<=DDR_RD_FIFO_CLEAR;
else
state<=state;
end
*/
(4)DDR_RD_FIFO_CLEAR
//延时10个节拍
always@(posedge clk or posedge reset)begin
if(reset)
rdfifo_clr_cnt<=0;
else if(state==DDR_RD_FIFO_CLEAR)//如果进入了清 fifo 状态
begin
if(rdfifo_clr_cnt==9)
rdfifo_clr_cnt<=5'd9;
else
rdfifo_clr_cnt<=rdfifo_clr_cnt+1'b1;
end
else
rdfifo_clr_cnt<=5'd0;
end
//给清FIFO信号足够的拉高时间
always@(posedge clk or posedge reset)begin
if (reset)
rdfifo_clr<=0;
else if(state==DDR_RD_FIFO_CLEAR)
begin
if(rdfifo_clr_cnt==0||rdfifo_clr_cnt==1||rdfifo_clr_cnt==2)
rdfifo_clr<=1'b1;
else
rdfifo_clr<=1'b0;
end
else
rdfifo_clr<=1'b0;
end
/*状态切换DDR_RD_FIFO_CLEAR->DATA_SEND_START
begin
if(!rdfifo_empty && (rdfifo_clr_cnt==9))begin
state<=DATA_SEND_START;
end
else
state<=state;
end
*/
(5)DATA_SEND_START
/*状态切换DATA_SEND_START->DATA_SEND_WORKING
begin
state <= DATA_SEND_WORKING;
end
*/
(6)DATA_SEND_WORKING
//发送数据计数
always@(posedge clk or posedge reset)begin
if(reset)
send_data_cnt<=32'd0;
else if(state==IDLE)
send_data_cnt<=32'd0;
else if(rdfifo_rden)
send_data_cnt<=send_data_cnt+1;
else
send_data_cnt<=send_data_cnt;
end
//DDR数据存到以太网缓存
always@(posedge clk or posedge reset)
if(reset) begin
eth_fifo_wrreq <= 1'b0;
eth_fifo_wrdata <= 'd0;
end
else if(rdfifo_rden) begin
eth_fifo_wrreq <= 1'b1;
eth_fifo_wrdata <= rdfifo_dout;
end
else begin
eth_fifo_wrreq <= 1'b0;
eth_fifo_wrdata <= 'd0;
end
/*状态切换DATA_SEND_WORKING->IDLE、DATA_SEND_WORKING->DATA_SEND_WORKING
begin
if(send_data_cnt >= set_sample_num-1'b1) begin
rdfifo_rden <= 1'b0;
state <= IDLE;
end
else begin
rdfifo_rden <= 1'b1;
state <= DATA_SEND_WORKING;
end
end
*/
7.1.4 fifo_axi_adapter模块
看文章开头:Zynq—AD9238数据采集DDR3缓存千兆以太网发送实验(一)。
S_IDLE:
begin
if(start)
next_state = S_ARB;
else
next_state = S_IDLE;
end
module fifo_axi4_adapter #(
parameter FIFO_DW = 16 ,
parameter WR_AXI_BYTE_ADDR_BEGIN = 0 ,
parameter WR_AXI_BYTE_ADDR_END = 1023 ,
parameter RD_AXI_BYTE_ADDR_BEGIN = 0 ,
parameter RD_AXI_BYTE_ADDR_END = 1023 ,
parameter AXI_DATA_WIDTH = 128 ,
parameter AXI_ADDR_WIDTH = 28 ,
parameter AXI_ID = 4'b0000,
parameter AXI_BURST_LEN = 8'd31 //burst length = 32
)
(
input start ,
// clock reset
input clk ,
input reset ,
// wr_fifo wr Interface
input wrfifo_clr ,
input wrfifo_clk ,
input wrfifo_wren ,
input [FIFO_DW-1:0] wrfifo_din ,
output wrfifo_full ,
output [15:0] wrfifo_wr_cnt ,
// rd_fifo rd Interface
input rdfifo_clr ,
input rdfifo_clk ,
input rdfifo_rden ,
output [FIFO_DW-1:0] rdfifo_dout ,
output rdfifo_empty ,
output [15:0] rdfifo_rd_cnt ,
// Master Interface Write Address Ports
output [3:0] m_axi_awid ,
output [AXI_ADDR_WIDTH-1:0] m_axi_awaddr ,
output [7:0] m_axi_awlen ,
output [2:0] m_axi_awsize ,
output [1:0] m_axi_awburst ,
output [0:0] m_axi_awlock ,
output [3:0] m_axi_awcache ,
output [2:0] m_axi_awprot ,
output [3:0] m_axi_awqos ,
output [3:0] m_axi_awregion,
output m_axi_awvalid ,
input m_axi_awready ,
// Master Interface Write Data Ports
output [AXI_DATA_WIDTH-1:0] m_axi_wdata ,
output [AXI_DATA_WIDTH/8-1:0] m_axi_wstrb ,
output m_axi_wlast ,
output m_axi_wvalid ,
input m_axi_wready ,
// Master Interface Write Response Ports
input [3:0] m_axi_bid ,
input [1:0] m_axi_bresp ,
input m_axi_bvalid ,
output m_axi_bready ,
// Master Interface Read Address Ports
output [3:0] m_axi_arid ,
output [AXI_ADDR_WIDTH-1:0] m_axi_araddr ,
output [7:0] m_axi_arlen ,
output [2:0] m_axi_arsize ,
output [1:0] m_axi_arburst ,
output [0:0] m_axi_arlock ,
output [3:0] m_axi_arcache ,
output [2:0] m_axi_arprot ,
output [3:0] m_axi_arqos ,
output [3:0] m_axi_arregion,
output m_axi_arvalid ,
input m_axi_arready ,
// Master Interface Read Data Ports
input [3:0] m_axi_rid ,
input [AXI_DATA_WIDTH-1:0] m_axi_rdata ,
input [1:0] m_axi_rresp ,
input m_axi_rlast ,
input m_axi_rvalid ,
output m_axi_rready
);
7.1.5 eth_send_data 模块
将DDR读出的ADC数据发送到电脑端。
(1)fifo_tx模块
First Word Fall Through( FWFT)可以不需要读命令, 自动将最新的数据放在 dout 上。
(2)eth_send_ctrl模块
以太网帧最大长度 1518 字节(数据段 1500 字节) , 其中数据段 1500 字节还包括 20 字节 IP 报文头部和 8 字节 UDP 报文头部, 所以数据帧发送的ACM9238 采集的数据最大长度为 1472 字节。
always@(posedge clk125M or negedge reset_n)
if(!reset_n) begin
pkt_tx_en <= 1'd0;
pkt_length <= 16'd0;
data_num <= 32'd0;
state <= 0;
cnt_dly_time <= 28'd0;
end
else begin
case(state)
0://得到 pkt_length 信号的初始值
begin
if(restart_req)begin
data_num <= total_data_num;
if((total_data_num << 1) >= 16'd1472)begin
pkt_length <= 16'd1472; //一个数据2个字节
state <= 1;
end
else if((total_data_num << 1) > 0)begin
pkt_length <= total_data_num << 1; //一个数据2个字节
state <= 1;
end
else begin
state <= 0;
end
end
end
1:
begin
if(fifo_rd_cnt >= (pkt_length -2)) begin
pkt_tx_en <= 1'd1;
state <= 2;
end
else begin
state <= 1;
pkt_tx_en <= 1'd0;
end
end
2:
begin
pkt_tx_en <= 1'd0;
if(eth_tx_done)begin
data_num <= data_num - pkt_length/2;
state <= 3;
end
end
3:
if(cnt_dly_time >= cnt_dly_min)begin
state <= 4;
cnt_dly_time <= 28'd0;
end
else begin
cnt_dly_time <= cnt_dly_time + 1'b1;
state <= 3;
end
4:
begin
if(data_num * 2 >= 16'd1472)begin
pkt_length <= 16'd1472;
state <= 1;
end
else if(data_num * 2 > 0)begin
pkt_length <= data_num * 2;
state <= 1;
end
else begin
state <= 0;
end
end
default:state <= 0;
endcase
end