题解 | #同步FIFO#
同步FIFO
https://www.nowcoder.com/practice/3ece2bed6f044ceebd172a7bf5cfb416
`timescale 1ns/1ns /**********************************RAM************************************/ module dual_port_RAM #(parameter DEPTH = 16, parameter WIDTH = 8)( input wclk ,input wenc ,input [$clog2(DEPTH)-1:0] waddr //深度对2取对数,得到地址的位宽。 ,input [WIDTH-1:0] wdata //数据写入 ,input rclk ,input renc ,input [$clog2(DEPTH)-1:0] raddr //深度对2取对数,得到地址的位宽。 ,output reg [WIDTH-1:0] rdata //数据输出 ); reg [WIDTH-1:0] RAM_MEM [0:DEPTH-1]; always @(posedge wclk) begin if(wenc) RAM_MEM[waddr] <= wdata; end always @(posedge rclk) begin if(renc) rdata <= RAM_MEM[raddr]; end endmodule /**********************************SFIFO************************************/ module sfifo#( parameter WIDTH = 8, parameter DEPTH = 16 )( input clk , input rst_n , input winc ,//写使能 input rinc ,//读使能 input [WIDTH-1:0] wdata ,//写数据 output reg wfull ,//写满信号 output reg rempty ,//读空信号 output wire [WIDTH-1:0] rdata//读数据 ); reg [$clog2(DEPTH):0] waddr; reg [$clog2(DEPTH):0] raddr; always @(posedge clk or negedge rst_n) begin if(!rst_n) begin waddr <= 0; end else begin waddr <= (winc && !wfull) ? waddr + 1 : waddr; end end always @(posedge clk or negedge rst_n) begin if(!rst_n) begin raddr <= 0; end else begin raddr <= (rinc && !rempty) ? raddr + 1 : raddr; end end always @(posedge clk or negedge rst_n)begin if(!rst_n)begin wfull<=0; rempty<=0; end else begin wfull<=(raddr=={~waddr[$clog2(DEPTH)],waddr[$clog2(DEPTH)-1:0]}); rempty<=(raddr==waddr);//读空,即读地址等于写地址 end end dual_port_RAM #(.DEPTH(DEPTH),.WIDTH(WIDTH)) U_dual_port_RAM ( .wclk(clk), .wenc(winc &~wfull),//写使能为1且未写满才能写 .waddr(waddr), //写地址 .wdata(wdata), //数据写入 .rclk(clk), .renc(rinc & ~rempty),//读使能为1且不是空 .raddr(raddr), //读地址 .rdata(rdata) //数据输出 ); endmodule