X-Git-Url: http://git.joshuawise.com/fpgaboy.git/blobdiff_plain/b4f3ac35e69b7d5adf57959902abe2a104b42f4f..6ba4cfea4b24fdd898e90ebd55e95ad43d5d21d4:/Soundcore.v

diff --git a/Soundcore.v b/Soundcore.v
new file mode 100644
index 0000000..172ed4f
--- /dev/null
+++ b/Soundcore.v
@@ -0,0 +1,71 @@
+`define ADDR_NR50 16'hFF24
+`define ADDR_NR51 16'hFF25
+`define ADDR_NR52 16'hFF26
+
+module Soundcore(
+	input core_clk,
+	input wr,
+	input rd,
+	input [15:0] addr,
+	inout [7:0] data,
+	output reg snd_data_l,
+	output reg snd_data_r
+	);
+
+	reg [7:0] nr50,nr51,nr52;
+	reg [3:0] pwmcnt;
+	reg [4:0] cntclk;
+	reg [13:0] lenclk;
+	wire [3:0] sndout1,sndout2,sndout3,sndout4;
+	wire [3:0] right_snd = nr51[0] ? sndout1 : 4'b0;
+	wire [3:0] left_snd = nr51[4] ? sndout1 : 4'b0;
+
+	assign sndout3 = 0;
+	assign sndout4 = 0;
+
+	assign data = rd ?
+	                 addr == `ADDR_NR50 ? nr50 :
+	                 addr == `ADDR_NR51 ? nr51 :
+	                 addr == `ADDR_NR52 ? nr52 : 8'bzzzzzzzz
+		      : 8'bzzzzzzzz;
+
+	always @ (negedge core_clk) begin
+		if(wr) begin
+			case(addr)
+			`ADDR_NR50: nr50 <= data;
+			`ADDR_NR51: nr51 <= data;
+			`ADDR_NR52: nr52 <= {data[7],3'b1,data[3:0]};
+			endcase
+		end
+		cntclk <= cntclk + 1;
+		lenclk <= lenclk + 1;
+		pwmcnt <= pwmcnt + 1; 
+		snd_data_l <= (pwmcnt <= left_snd) ? 1 : 0;
+		snd_data_r <= (pwmcnt <= right_snd) ? 1 : 0;
+	end
+
+	Sound1(
+		.core_clk(core_clk),
+		.wr(wr),
+		.rd(rd),
+		.addr(addr),
+		.data(data),
+		.cntclk(cntclk[4]),
+		.lenclk(lenclk[13]),
+		.en(nr52[7] & nr52[0]),
+		.snd_data(sndout1)
+	);
+	
+	Sound2(
+		.core_clk(core_clk),
+		.wr(wr),
+		.rd(rd),
+		.addr(addr),
+		.data(data),
+		.cntclk(cntclk[4]),
+		.lenclk(lenclk[13]),
+		.en(nr52[7] & nr52[0]),
+		.snd_data(sndout2)
+	);
+
+endmodule