OpenFPGA/openfpga_flow/benchmarks/iwls2005/ac97_ctrl/rtl/ac97_rst.v

104 lines
3.7 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// WISHBONE AC 97 Controller Reset Module ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/ac97_ctrl/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2001 Rudolf Usselmann ////
//// 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_rst.v,v 1.1 2001/08/03 06:54:50 rudi Exp $
//
// $Date: 2001/08/03 06:54:50 $
// $Revision: 1.1 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: ac97_rst.v,v $
// Revision 1.1 2001/08/03 06:54:50 rudi
//
//
// - Changed to new directory structure
//
// Revision 1.1.1.1 2001/05/19 02:29:19 rudi
// Initial Checkin
//
//
//
//
`include "ac97_defines.v"
module ac97_rst(clk, rst, rst_force, ps_ce, ac97_rst_);
input clk, rst;
input rst_force;
output ps_ce;
output ac97_rst_;
reg ac97_rst_;
reg [2:0] cnt;
wire ce;
wire to;
reg [5:0] ps_cnt;
wire ps_ce;
always @(posedge clk or negedge rst)
if(!rst) ac97_rst_ <= #1 0;
else
if(rst_force) ac97_rst_ <= #1 0;
else
if(to) ac97_rst_ <= #1 1;
assign to = (cnt == `AC97_RST_DEL);
always @(posedge clk or negedge rst)
if(!rst) cnt <= #1 0;
else
if(rst_force) cnt <= #1 0;
else
if(ce) cnt <= #1 cnt + 1;
assign ce = ps_ce & (cnt != `AC97_RST_DEL);
always @(posedge clk or negedge rst)
if(!rst) ps_cnt <= #1 0;
else
if(ps_ce | rst_force) ps_cnt <= #1 0;
else ps_cnt <= #1 ps_cnt + 1;
assign ps_ce = (ps_cnt == `AC97_250_PS);
endmodule