//---------------------------------------------------------------------------- // Copyright (C) 2009 , Olivier Girard // // 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 authors nor the names of its 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 // //---------------------------------------------------------------------------- // // *File Name: omsp_sync_cell.v // // *Module Description: // Generic synchronizer for the openMSP430 // // *Author(s): // - Olivier Girard, olgirard@gmail.com // //---------------------------------------------------------------------------- // $Rev: 103 $ // $LastChangedBy: olivier.girard $ // $LastChangedDate: 2011-03-05 15:44:48 +0100 (Sat, 05 Mar 2011) $ //---------------------------------------------------------------------------- module omsp_sync_cell ( // OUTPUTs data_out, // Synchronized data output // INPUTs clk, // Receiving clock data_in, // Asynchronous data input rst // Receiving reset (active high) ); // OUTPUTs //========= output data_out; // Synchronized data output // INPUTs //========= input clk; // Receiving clock input data_in; // Asynchronous data input input rst; // Receiving reset (active high) //============================================================================= // 1) SYNCHRONIZER //============================================================================= reg [1:0] data_sync; always @(posedge clk or posedge rst) if (rst) data_sync <= 2'b00; else data_sync <= {data_sync[0], data_in}; assign data_out = data_sync[1]; endmodule // omsp_sync_cell