1
0
mirror of https://github.com/sehugg/8bitworkshop.git synced 2024-11-28 23:49:20 +00:00
8bitworkshop/presets/verilog/starfield.v
2018-02-14 13:38:50 -06:00

40 lines
817 B
Verilog

`include "hvsync_generator.v"
`include "lfsr.v"
module top(clk, reset, hsync, vsync, rgb);
input clk, reset;
output hsync, vsync;
output [2:0] rgb;
wire display_on;
wire [8:0] hpos;
wire [8:0] vpos;
wire [15:0] lfsr;
hvsync_generator hvsync_gen(
.clk(clk),
.reset(reset),
.hsync(hsync),
.vsync(vsync),
.display_on(display_on),
.hpos(hpos),
.vpos(vpos)
);
wire star_enable = !hpos[8] & !vpos[8];
// LFSR with period = 2^16-1 = 256*256-1
LFSR #(16,16'b1000000001011,0) lfsr_gen(
.clk(clk),
.reset(reset),
.enable(star_enable),
.lfsr(lfsr));
wire star_on = &lfsr[15:9];
wire r = display_on && star_on && lfsr[0];
wire g = display_on && star_on && lfsr[1];
wire b = display_on && star_on && lfsr[2];
assign rgb = {b,g,r};
endmodule