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//////////////////////////////////////////////////////////////////////
//// ////
//// uart_TX_FIFO.v ////
//// ////
//// ////
//// This file is part of the "UART 16550 compatible" project ////
//// http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Documentation related to this project: ////
//// - http://www.opencores.org/cores/uart16550/ ////
//// ////
//// Projects compatibility: ////
//// - WISHBONE ////
//// RS232 Protocol ////
//// 16550D uart (mostly supported) ////
//// ////
//// Overview (main Features): ////
//// UART core WISHBONE interface. ////
//// ////
//// Known problems (limits): ////
//// Inserts one wait state on all transfers. ////
//// Note affected signals and the way they are affected. ////
//// ////
//// To Do: ////
//// Nothing. ////
//// ////
//// Author(s): ////
//// - gorban@opencores.org ////
//// - Jacob Gorban ////
//// ////
//// Created: 2001/05/12 ////
//// Last Updated: 2001/05/17 ////
//// (See log for the revision history) ////
//// ////
//// ////
//////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000 Jacob Gorban, gorban@opencores.org ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer. ////
//// ////
//// This source file is free software; you can redistribute it ////
//// and/or modify it under the terms of the GNU Lesser General ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any ////
//// later version. ////
//// ////
//// This source is distributed in the hope that it will be ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
//// PURPOSE. See the GNU Lesser General Public License for more ////
//// details. ////
//// ////
//// You should have received a copy of the GNU Lesser General ////
//// Public License along with this source; if not, download it ////
//// from http://www.opencores.org/lgpl.shtml ////
//// ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: uart_wb.v,v $
// Revision 1.4 2001/05/31 20:08:01 gorban
// FIFO changes and other corrections.
//
// Revision 1.3 2001/05/21 19:12:01 gorban
// Corrected some Linter messages.
//
// Revision 1.2 2001/05/17 18:34:18 gorban
// First 'stable' release. Should be sythesizable now. Also added new header.
//
// Revision 1.0 2001-05-17 21:27:13+02 jacob
// Initial revision
//
//
// UART core WISHBONE interface
//
// Author: Jacob Gorban (jacob.gorban@flextronicssemi.com)
// Company: Flextronics Semiconductor
//
`include "timescale.v"
module uart_wb (clk,
wb_rst_i,
wb_we_i, wb_stb_i, wb_cyc_i, wb_ack_o,
we_o, re_o // Write and read enable output for the core
);
input clk;
// WISHBONE interface
input wb_rst_i;
input wb_we_i;
input wb_stb_i;
input wb_cyc_i;
output wb_ack_o;
output we_o;
output re_o;
wire we_o;
reg wb_ack_o;
always @(posedge clk or posedge wb_rst_i)
begin
if (wb_rst_i)
begin
wb_ack_o <= #1 1'b0;
end
else
begin
// wb_ack_o <= #1 wb_stb_i & wb_cyc_i; // 1 clock wait state on all transfers
wb_ack_o <= #1 wb_stb_i & wb_cyc_i & ~wb_ack_o; // 1 clock wait state on all transfers
end
end
assign we_o = wb_we_i & wb_cyc_i & wb_stb_i; //WE for registers
assign re_o = ~wb_we_i & wb_cyc_i & wb_stb_i; //RE for registers
endmodule
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