| 1 |
7 |
dgisselq |
////////////////////////////////////////////////////////////////////////////////
|
| 2 |
|
|
//
|
| 3 |
|
|
// Filename: wbgpio.v
|
| 4 |
|
|
//
|
| 5 |
|
|
// Project: CMod S6 System on a Chip, ZipCPU demonstration project
|
| 6 |
|
|
//
|
| 7 |
|
|
// Purpose: A General Purpose Input/Output controller. This controller
|
| 8 |
|
|
// allows a user to read the current state of the 16-GPIO input
|
| 9 |
|
|
// pins, or to set the state of the 16-GPIO output pins. Specific numbers
|
| 10 |
|
|
// of pins are configurable from 1-16.
|
| 11 |
|
|
//
|
| 12 |
|
|
// Unlike other controllers, this controller offers no capability to
|
| 13 |
|
|
// change input/output direction, or to implement pull-up or pull-down
|
| 14 |
|
|
// resistors. It simply changes and adjusts the values going out the
|
| 15 |
|
|
// output pins, while allowing a user to read the values on the input
|
| 16 |
|
|
// pins.
|
| 17 |
|
|
//
|
| 18 |
|
|
// Any change of an input pin value will result in the generation of an
|
| 19 |
|
|
// interrupt signal.
|
| 20 |
|
|
//
|
| 21 |
|
|
// Creator: Dan Gisselquist, Ph.D.
|
| 22 |
|
|
// Gisselquist Technology, LLC
|
| 23 |
|
|
//
|
| 24 |
|
|
////////////////////////////////////////////////////////////////////////////////
|
| 25 |
|
|
//
|
| 26 |
|
|
// Copyright (C) 2015-2016, Gisselquist Technology, LLC
|
| 27 |
|
|
//
|
| 28 |
|
|
// This program is free software (firmware): you can redistribute it and/or
|
| 29 |
|
|
// modify it under the terms of the GNU General Public License as published
|
| 30 |
|
|
// by the Free Software Foundation, either version 3 of the License, or (at
|
| 31 |
|
|
// your option) any later version.
|
| 32 |
|
|
//
|
| 33 |
|
|
// This program is distributed in the hope that it will be useful, but WITHOUT
|
| 34 |
|
|
// ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY or
|
| 35 |
|
|
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
| 36 |
|
|
// for more details.
|
| 37 |
|
|
//
|
| 38 |
|
|
// You should have received a copy of the GNU General Public License along
|
| 39 |
|
|
// with this program. (It's in the $(ROOT)/doc directory, run make with no
|
| 40 |
|
|
// target there if the PDF file isn't present.) If not, see
|
| 41 |
|
|
// <http://www.gnu.org/licenses/> for a copy.
|
| 42 |
|
|
//
|
| 43 |
|
|
// License: GPL, v3, as defined and found on www.gnu.org,
|
| 44 |
|
|
// http://www.gnu.org/licenses/gpl.html
|
| 45 |
|
|
//
|
| 46 |
|
|
//
|
| 47 |
|
|
////////////////////////////////////////////////////////////////////////////////
|
| 48 |
|
|
//
|
| 49 |
|
|
//
|
| 50 |
2 |
dgisselq |
module wbgpio(i_clk, i_wb_cyc, i_wb_stb, i_wb_we, i_wb_data, o_wb_data,
|
| 51 |
|
|
i_gpio, o_gpio, o_int);
|
| 52 |
|
|
parameter NIN=16, NOUT=16, DEFAULT=16'h00;
|
| 53 |
|
|
input i_clk;
|
| 54 |
|
|
//
|
| 55 |
|
|
input i_wb_cyc, i_wb_stb, i_wb_we;
|
| 56 |
|
|
input [31:0] i_wb_data;
|
| 57 |
|
|
output wire [31:0] o_wb_data;
|
| 58 |
|
|
//
|
| 59 |
|
|
input [(NIN-1):0] i_gpio;
|
| 60 |
|
|
output reg [(NOUT-1):0] o_gpio;
|
| 61 |
|
|
//
|
| 62 |
|
|
output reg o_int;
|
| 63 |
|
|
|
| 64 |
|
|
// 9LUT's, 16 FF's
|
| 65 |
|
|
always @(posedge i_clk)
|
| 66 |
46 |
dgisselq |
if ((i_wb_stb)&&(i_wb_we))
|
| 67 |
2 |
dgisselq |
o_gpio <= ((o_gpio)&(~i_wb_data[(NOUT+16-1):16]))
|
| 68 |
|
|
|((i_wb_data[(NOUT-1):0])&(i_wb_data[(NOUT+16-1):16]));
|
| 69 |
|
|
|
| 70 |
|
|
reg [(NIN-1):0] x_gpio, r_gpio;
|
| 71 |
|
|
// 3 LUTs, 33 FF's
|
| 72 |
|
|
always @(posedge i_clk)
|
| 73 |
|
|
begin
|
| 74 |
|
|
x_gpio <= i_gpio;
|
| 75 |
|
|
r_gpio <= x_gpio;
|
| 76 |
|
|
o_int <= (x_gpio != r_gpio);
|
| 77 |
|
|
end
|
| 78 |
|
|
|
| 79 |
|
|
assign o_wb_data = { {(16-NIN){1'b0}}, r_gpio,
|
| 80 |
|
|
{(16-NOUT){1'b0}}, o_gpio };
|
| 81 |
|
|
endmodule
|
