/*
Wishlist in order of importance and practicality.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1	GPIO						hard wired
2	U(S)ART						hard wired or SPCx
3	video						hard wired or SPCx
4	PS/2						hard wired
5	32b timer					hard wired
6	2x 16b timers				hard wired
7	PWM timer					hard wired
8	LED driver					hard wired
9	sound						hard wired or SPCx
10	DMA							hard wired
11	USB							hard wired or SPCx
12	Ethernet					(SPCx or 16BC) with hard wired
13	3x FPGA or SPCx peripheral	hard wired or SPCx
14	LPC decoder?				hard wired or SPCx
15	LPC coder?					hard wired or SPCx
16	FPU							hard wired or SPCx or 16BC
17	RTC (RFC 2550 complient)	external
18	mass storage				external

xx	All-in-one serial communication module. Not sure where to put this.
*/

//GPIO
module GPIO(
	
	input clk,
	input out,
	input in,
	
	inout [15:0] data,
	inout [15:0] GPIO0,
	inout [15:0] GPIO1
);

reg [15:0] GPIOCR0 = 16'h0000;
reg [15:0] GPIOR0 = 16'h0000;
reg [15:0] GPIOCR1 = 16'h0000;
reg [15:0] GPIOR1 = 16'h0000;

assign data = (in & (addr == 16'hFE00)) ? GPIOR0 : 16'hz;
assign data = (in & (addr == 16'hFE01)) ? GPIOCR0 : 16'hz;
assign data = (in & (addr == 16'hFE02)) ? GPIOR1 : 16'hz;
assign data = (in & (addr == 16'hFE03)) ? GPIOCR1 : 16'hz;

always @(posedge clk) begin
	if (reset) begin
		GPIOCR0 <= 16'bz;
		GPIOR0 <= 16'b0000;
	end else if (out) begin
		if (addr == 16'hFE00) begin
			GPIOR0 <= data;
		end else if (addr == 16'hFE01) begin
			GPIOCR0 <= data;
		end
	end
end

always @(posedge clk) begin
	if (reset) begin
		GPIOCR1 <= 16'bz;
		GPIOR1 <= 16'b0000;
	end else if (out) begin
		if (addr == 16'hFE02) begin
			GPIOR1 <= data;
		end else if (addr == 16'hFE03) begin
			GPIOCR1 <= data;
		end
	end
end

endmodule

module USART(
	input clk,
	input RxD,
	input CTS,
	
	inout [15:0] data,
	inout SCLK,
	
	output TxD,
	output RTS
);

endmodule