yayacemu/chip8.sv

141 lines
2.4 KiB
Systemverilog

module chip8 (
input wire clk_in,
input wire rst_in
);
bit [31:0] vram[0:2047];
bit [7:0] memory[0:4095];
bit keyboard[15:0];
bit [7:0] sound_timer;
bit [15:0] program_counter;
int cycle_counter;
bit [7:0] random_number;
beeper beeper (sound_timer);
cpu cpu (
rst_in,
memory,
clk_in,
keyboard,
random_number,
cycle_counter,
program_counter,
vram,
sound_timer
);
gpu gpu (vram);
keyboard kb (
clk_in,
keyboard
);
rng randy (
clk_in,
program_counter,
keyboard,
cycle_counter,
random_number
);
rom_loader loader (memory);
always_ff @(posedge clk_in) begin
if (rst_in) begin
bit [7:0] fontset[79:0] = {
8'hF0,
8'h90,
8'h90,
8'h90,
8'hF0, // 0
8'h20,
8'h60,
8'h20,
8'h20,
8'h70, // 1
8'hF0,
8'h10,
8'hF0,
8'h80,
8'hF0, // 2
8'hF0,
8'h10,
8'hF0,
8'h10,
8'hF0, // 3
8'h90,
8'h90,
8'hF0,
8'h10,
8'h10, // 4
8'hF0,
8'h80,
8'hF0,
8'h10,
8'hF0, // 5
8'hF0,
8'h80,
8'hF0,
8'h90,
8'hF0, // 6
8'hF0,
8'h10,
8'h20,
8'h40,
8'h40, // 7
8'hF0,
8'h90,
8'hF0,
8'h90,
8'hF0, // 8
8'hF0,
8'h90,
8'hF0,
8'h10,
8'hF0, // 9
8'hF0,
8'h90,
8'hF0,
8'h90,
8'h90, // A
8'hE0,
8'h90,
8'hE0,
8'h90,
8'hE0, // B
8'hF0,
8'h80,
8'h80,
8'h80,
8'hF0, // C
8'hE0,
8'h90,
8'h90,
8'h90,
8'hE0, // D
8'hF0,
8'h80,
8'hF0,
8'h80,
8'hF0, // E
8'hF0,
8'h80,
8'hF0,
8'h80,
8'h80 // F
};
// Load fontset into memory
for (int i = 0; i < 80; i++) begin
memory[i] = fontset[79-i];
end
// Initialize keyboard bits
for (int i = 0; i < 15; i++) begin
keyboard[i] = 0;
end
end
end
endmodule