Subversion Repositories wb4pb

////////////////////////////////////////////////////////////////////////////////

// This sourcecode is released under BSD license.

// Please see http://www.opensource.org/licenses/bsd-license.php for details!

////////////////////////////////////////////////////////////////////////////////

//

// Copyright (c) 2010, Stefan Fischer <Ste.Fis@OpenCores.org>

// All rights reserved.

//

// Redistribution and use in source and binary forms, with or without 

// modification, are permitted provided that the following conditions are met:

//

//  * Redistributions of source code must retain the above copyright notice, 

//    this list of conditions and the following disclaimer.

//  * Redistributions in binary form must reproduce the above copyright notice,

//    this list of conditions and the following disclaimer in the documentation

//    and/or other materials provided with the distribution. 

//  * Neither the name of the author nor the names of his contributors may be 

//    used to endorse or promote products derived from this software without 

//    specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 

// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 

// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 

// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 

// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 

// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 

// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 

// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 

// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 

// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 

// POSSIBILITY OF SUCH DAMAGE.

//

////////////////////////////////////////////////////////////////////////////////

// filename: picoblaze_wb_gpio.v

// description: synthesizable PicoBlaze (TM) general purpose i/o example using 

//              wishbone

// todo4user: add other modules as needed

// version: 0.0.0

// changelog: - 0.0.0, initial release

//            - ...

////////////////////////////////////////////////////////////////////////////////

module picoblaze_wb_gpio (

  p_rst_n_i,

  p_clk_i,

  p_gpio_io

);

  input p_rst_n_i;

  wire  p_rst_n_i;

  input p_clk_i;

  wire  p_clk_i;

  inout[7:0] p_gpio_io;

  wire [7:0] p_gpio_io;

  reg rst;

  wire clk;

  wire wb_cyc;

  wire wb_stb;

  wire wb_we;

  wire[7:0] wb_adr;

  wire[7:0] wb_dat_m2s;

  wire[7:0] wb_dat_s2m;

  wire wb_ack;

  wire pb_write_strobe;

  wire pb_read_strobe;

  wire[7:0] pb_port_id;

  wire[7:0] pb_in_port;

  wire[7:0] pb_out_port;

  wire[17:0] instruction;

  wire[9:0] address;

  wire interrupt;

  wire interrupt_ack;

  wire[7:0] gpio_in;

  wire[7:0] gpio_out;

  wire[7:0] gpio_oe;

  reg [7:0] gpio;

  parameter IS_INPUT = 1'b0;

  parameter IS_OUTPUT = ! IS_INPUT;

  integer i;

  // reset synchronisation

  always@(posedge clk)

    rst <= ! p_rst_n_i;

  assign clk = p_clk_i;

  // module instances

  ///////////////////

  kcpsm3 inst_kcpsm3 (

    .address(address),

    .instruction(instruction),

    .port_id(pb_port_id),

    .write_strobe(pb_write_strobe),

    .out_port(pb_out_port),

    .read_strobe(pb_read_strobe),

    .in_port(pb_in_port),

    .interrupt(interrupt),

    .interrupt_ack(interrupt_ack),

    .reset(rst),

    .clk(clk)

  );

  pbwbgpio inst_pbwbgpio (

    .address(address),

    .instruction(instruction),

    .clk(clk)

  );

  wbm_picoblaze inst_wbm_picoblaze (

    .rst(rst),

    .clk(clk),

    .wbm_cyc_o(wb_cyc),

    .wbm_stb_o(wb_stb),

    .wbm_we_o(wb_we),

    .wbm_adr_o(wb_adr),

    .wbm_dat_m2s_o(wb_dat_m2s),

    .wbm_dat_s2m_i(wb_dat_s2m),

    .wbm_ack_i(wb_ack),

    .pb_port_id_i(pb_port_id),

    .pb_write_strobe_i(pb_write_strobe),

    .pb_out_port_i(pb_out_port),

    .pb_read_strobe_i(pb_read_strobe),

    .pb_in_port_o(pb_in_port)

  );

  wbs_gpio inst_wbs_gpio (

    .rst(rst),

    .clk(clk),

    .wbs_cyc_i(wb_cyc),

    .wbs_stb_i(wb_stb),

    .wbs_we_i(wb_we),

    .wbs_adr_i(wb_adr),

    .wbs_dat_m2s_i(wb_dat_m2s),

    .wbs_dat_s2m_o(wb_dat_s2m),

    .wbs_ack_o(wb_ack),

    .gpio_in_i(gpio_in),

    .gpio_out_o(gpio_out),

    .gpio_oe_o(gpio_oe)

  );

  // i/o buffer generation

  assign gpio_in = p_gpio_io;

  always@(gpio_oe or gpio_out)

    for (i = 0; i <= 7; i = i + 1)

      if (gpio_oe[i] == IS_OUTPUT)

        gpio[i] = gpio_out[i];

      else

        gpio[i] = 1'bZ;

  assign p_gpio_io = gpio;

endmodule