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//
// Copyright 2011-2012 Ettus Research LLC
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// This module takes the settings bus on one clock domain and crosses it over to another domain
// Typically it will be used with the input settings bus on the wishbone clock, and either
// the system or dsp clock on the output side
module settings_bus_crossclock
#(parameter FLOW_CTRL=0, parameter AWIDTH=8, parameter DWIDTH=32)
(input clk_i, input rst_i, input set_stb_i, input [AWIDTH-1:0] set_addr_i, input [DWIDTH-1:0] set_data_i,
input clk_o, input rst_o, output set_stb_o, output [AWIDTH-1:0] set_addr_o, output [DWIDTH-1:0] set_data_o, input blocked);
wire nfull, nempty;
axi_fifo_2clk #(.WIDTH(AWIDTH + DWIDTH), .SIZE(0)) settings_fifo
(.reset(rst_i),
.i_aclk(clk_i), .i_tdata({set_addr_i,set_data_i}), .i_tvalid(set_stb_i), .i_tready(nfull),
.o_aclk(clk_o), .o_tdata({set_addr_o,set_data_o}), .o_tready(set_stb_o), .o_tvalid(nempty));
assign set_stb_o = nempty & (~blocked | ~FLOW_CTRL);
endmodule // settings_bus_crossclock
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