Subversion Repositories s80186

// Copyright Jamie Iles, 2017

//

// This file is part of s80x86.

//

// s80x86 is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// s80x86 is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

// GNU General Public License for more details.

//

// You should have received a copy of the GNU General Public License

// along with s80x86.  If not, see .

`ifndef FONT_ROM_PATH

`define FONT_ROM_PATH "."

`endif

module FontColorLUT(input logic clk,

                    input logic render_cursor,

                    input logic [7:0] glyph,

                    input logic [2:0] glyph_row,

                    input logic [2:0] glyph_col,

                    input logic [3:0] foreground,

                    input logic [3:0] background,

                    output logic [3:0] r,

                    output logic [3:0] g,

                    output logic [3:0] b);

// 64 bits per character, 256 characters

logic font_rom[16384];

initial $readmemb({{`FONT_ROM_PATH, "/font.bin"}}, font_rom);

logic font_bit;

wire [13:0] font_mem_addr = {glyph, glyph_row[2:0], glyph_col[2:0]};

wire [11:0] foreground_rgb;

wire [11:0] background_rgb;

reg [11:0] color_lut [0:15] = '{

    12'h0_0_0, // black

    12'h0_0_a, // blue

    12'h0_a_0, // green

    12'h0_a_a, // cyan

    12'ha_0_0, // red

    12'ha_0_a, // magenta

    12'ha_5_0, // brown

    12'ha_a_a, // white

    12'h5_5_5, // gray

    12'h5_5_f, // bright blue

    12'h5_f_5, // bright green

    12'h5_f_f, // bright cyan

    12'hf_5_5, // bright red

    12'hf_5_f, // bright magenta

    12'hf_f_5, // yellow

    12'hf_f_f  // bright white

};

always_ff @(posedge clk) begin

    foreground_rgb <= color_lut[foreground];

    background_rgb <= color_lut[background];

end

assign {r, g, b} = font_bit ^ render_cursor ? foreground_rgb : background_rgb;

always_ff @(posedge clk)

    font_bit <= font_rom[font_mem_addr];

endmodule