+module ROM(
+ input [15:0] address,
+ inout [7:0] data,
+ input clk,
+ input wr, rd);
+
+ reg [7:0] rom [2047:0];
+ initial $readmemh("rom.hex", rom);
+
+ wire decode = address[15:13] == 0;
+ wire [7:0] odata = rom[address[11:0]];
+ assign data = (rd && decode) ? odata : 8'bzzzzzzzz;
+ //assign data = rd ? odata : 8'bzzzzzzzz;
+endmodule
+
+module InternalRAM(
+ input [15:0] address,
+ inout [7:0] data,
+ input clk,
+ input wr, rd);
+
+ reg [7:0] ram [8191:0];
+
+ wire decode = (address >= 16'hC000) && (address < 16'hFE00);
+ reg [7:0] odata;
+ wire idata = data;
+ assign data = (rd && decode) ? odata : 8'bzzzzzzzz;
+
+ always @(negedge clk)
+ begin
+ if (decode && rd)
+ odata <= ram[address[12:0]];
+ else if (decode && wr)
+ ram[address[12:0]] <= data;
+ end
+endmodule
+
+module Switches(
+ input [15:0] address,
+ inout [7:0] data,
+ input clk,
+ input wr, rd,
+ input [7:0] switches,
+ output reg [7:0] ledout);
+
+ wire decode = address == 16'hFF51;
+ reg [7:0] odata;
+ wire idata = data;
+ assign data = (rd && decode) ? odata : 8'bzzzzzzzz;
+
+ always @(negedge clk)
+ begin
+ if (decode && rd)
+ odata <= switches;
+ else if (decode && wr)
+ ledout <= data;
+ end
+endmodule
+
+module CoreTop(
+ input xtal,
+ input [1:0] switches,
+ output wire [7:0] leds,
+ output serio,
+ output wire [3:0] digits,
+ output wire [7:0] seven);
+
+ wire clk;
+ //IBUFG ibuf (.O(clk), .I(iclk));
+
+ CPUDCM dcm (.CLKIN_IN(xtal), .CLKFX_OUT(clk));
+
+ wire [15:0] addr;
+ wire [7:0] data;
+ wire wr, rd;
+
+ wire [7:0] ledout;
+ assign leds = switches[1] ? (switches[0]?{rd,wr,addr[5:0]}:data[7:0])
+ : ledout;
+
+ GBZ80Core core(
+ .clk(clk),
+ .busaddress(addr),
+ .busdata(data),
+ .buswr(wr),
+ .busrd(rd));
+
+ ROM rom(
+ .address(addr),
+ .data(data),
+ .clk(clk),
+ .wr(wr),
+ .rd(rd));
+
+ AddrMon amon(
+ .addr(addr),
+ .clk(clk),
+ .digit(digits),
+ .out(seven)
+ );
+
+ Switches sw(
+ .address(addr),
+ .data(data),
+ .clk(clk),
+ .wr(wr),
+ .rd(rd),
+ .ledout(ledout),
+ .switches(0)
+ );
+
+ UART nouart (
+ .clk(clk),
+ .wr(wr),
+ .rd(rd),
+ .addr(addr),
+ .data(data),
+ .serial(serio)
+ );
+endmodule
+