题解 | #同步FIFO#
同步FIFO
http://www.nowcoder.com/practice/e5e86054a0ce4355b9dfc08238f25f5f
改动了一点DPRAM。。。
`timescale 1ns/1ns
/**********************************RAM************************************/
module dual_port_RAM #(parameter DEPTH = 16,
parameter WIDTH = 8)(
input clk
,input wenc
,input [$clog2(DEPTH)-1:0] waddr
,input [WIDTH-1:0] wdata
,input renc
,input [$clog2(DEPTH)-1:0] raddr
,output reg [WIDTH-1:0] rdata
);
reg [WIDTH-1:0] RAM_MEM [0:DEPTH-1];
always @(posedge clk) begin
if(wenc)
RAM_MEM[waddr] <= wdata;
end
always @(posedge clk) 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 ,
input rinc ,
input [WIDTH-1:0] wdata ,
output reg wfull ,
output reg rempty ,
output wire [WIDTH-1:0] rdata
);
reg [$clog2(DEPTH):0] cnt;
wire wenc, renc;
reg [$clog2(DEPTH)-1:0] waddr, raddr;
assign wenc = (winc & !wfull);
assign renc = (rinc & !rempty);
dual_port_RAM #(.WIDTH(WIDTH), .DEPTH(DEPTH))
u_DPRAM (
.clk(clk), .wenc(wenc), .renc(renc),
.wdata(wdata), .rdata(rdata),
.raddr(raddr), .waddr(waddr));
always @(posedge clk or negedge rst_n) begin
if (!rst_n) begin
wfull <= 1'b0;
end else if (cnt == DEPTH) begin
wfull <= 1'b1;
end else begin
wfull <= 1'b0;
end
end
always @(posedge clk or negedge rst_n) begin
if (!rst_n) begin
rempty <= 1'b0;
end else if (cnt == 'b0) begin
rempty <= 1'b1;
end else begin
rempty <= 1'b0;
end
end
always @(posedge clk or negedge rst_n) begin
if (!rst_n) begin
cnt <= 'b0;
end else if (wenc & !renc) begin
cnt <= cnt + 1'b1;
end else if (renc & !wenc) begin
cnt <= cnt - 1'b1;
end
end
always @(posedge clk or negedge rst_n) begin
if (!rst_n) begin
waddr <= 'b0;
end else if (wenc) begin
waddr <= waddr +1'b1;
end
end
always @(posedge clk or negedge rst_n) begin
if (!rst_n) begin
raddr <= 'b0;
end else if (renc) begin
raddr <= raddr +1'b1;
end
end
endmodule