OpenFPGA/openfpga_flow/benchmarks/iwls2005/ac97_ctrl/rtl/ac97_sin.v

146 lines
4.5 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// WISHBONE AC 97 Controller ////
//// Serial Input Block ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/ac97_ctrl/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000-2002 Rudolf Usselmann ////
//// www.asics.ws ////
//// rudi@asics.ws ////
//// ////
//// 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 SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY ////
//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ////
//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ////
//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR ////
//// 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. ////
//// ////
/////////////////////////////////////////////////////////////////////
// CVS Log
//
// $Id: ac97_sin.v,v 1.2 2002/09/19 06:30:56 rudi Exp $
//
// $Date: 2002/09/19 06:30:56 $
// $Revision: 1.2 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: ac97_sin.v,v $
// Revision 1.2 2002/09/19 06:30:56 rudi
// Fixed a bug reported by Igor. Apparently this bug only shows up when
// the WB clock is very low (2x bit_clk). Updated Copyright header.
//
// Revision 1.1 2001/08/03 06:54:50 rudi
//
//
// - Changed to new directory structure
//
// Revision 1.1.1.1 2001/05/19 02:29:15 rudi
// Initial Checkin
//
//
//
//
`include "ac97_defines.v"
module ac97_sin(clk, rst,
out_le, slt0, slt1, slt2, slt3, slt4,
slt6,
sdata_in
);
input clk, rst;
// --------------------------------------
// Misc Signals
input [5:0] out_le;
output [15:0] slt0;
output [19:0] slt1;
output [19:0] slt2;
output [19:0] slt3;
output [19:0] slt4;
output [19:0] slt6;
// --------------------------------------
// AC97 Codec Interface
input sdata_in;
////////////////////////////////////////////////////////////////////
//
// Local Wires
//
reg sdata_in_r;
reg [19:0] sr;
reg [15:0] slt0;
reg [19:0] slt1;
reg [19:0] slt2;
reg [19:0] slt3;
reg [19:0] slt4;
reg [19:0] slt6;
////////////////////////////////////////////////////////////////////
//
// Output Registers
//
always @(posedge clk)
if(out_le[0]) slt0 <= #1 sr[15:0];
always @(posedge clk)
if(out_le[1]) slt1 <= #1 sr;
always @(posedge clk)
if(out_le[2]) slt2 <= #1 sr;
always @(posedge clk)
if(out_le[3]) slt3 <= #1 sr;
always @(posedge clk)
if(out_le[4]) slt4 <= #1 sr;
always @(posedge clk)
if(out_le[5]) slt6 <= #1 sr;
////////////////////////////////////////////////////////////////////
//
// Serial Shift Register
//
always @(negedge clk)
sdata_in_r <= #1 sdata_in;
always @(posedge clk)
sr <= #1 {sr[18:0], sdata_in_r };
endmodule