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//
// Copyright 2011 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/>.
//
// Note -- clocks must be synchronous (derived from the same source)
// Assumes alt_clk is running at a multiple of wb_clk
// Note -- assumes that the lower-16 bits will be requested first,
// and that the upper-16 bit request will come immediately after.
module wb_readback_mux_16LE
(input wb_clk_i,
input wb_rst_i,
input wb_stb_i,
input [15:0] wb_adr_i,
output [15:0] wb_dat_o,
output reg wb_ack_o,
input [31:0] word00,
input [31:0] word01,
input [31:0] word02,
input [31:0] word03,
input [31:0] word04,
input [31:0] word05,
input [31:0] word06,
input [31:0] word07,
input [31:0] word08,
input [31:0] word09,
input [31:0] word10,
input [31:0] word11,
input [31:0] word12,
input [31:0] word13,
input [31:0] word14,
input [31:0] word15
);
wire ack_next = wb_stb_i & ~wb_ack_o;
always @(posedge wb_clk_i)
if(wb_rst_i)
wb_ack_o <= 0;
else
wb_ack_o <= ack_next;
reg [31:0] data;
assign wb_dat_o = data[15:0];
always @(posedge wb_clk_i)
if (wb_adr_i[1] & ack_next) begin //upper half
data[15:0] <= data[31:16];
end
else if (~wb_adr_i[1] & ack_next) begin //lower half
case(wb_adr_i[5:2])
0 : data <= word00;
1 : data <= word01;
2 : data <= word02;
3 : data <= word03;
4 : data <= word04;
5 : data <= word05;
6 : data <= word06;
7 : data <= word07;
8 : data <= word08;
9 : data <= word09;
10: data <= word10;
11: data <= word11;
12: data <= word12;
13: data <= word13;
14: data <= word14;
15: data <= word15;
endcase // case(wb_adr_i[5:2])
end
endmodule // wb_readback_mux
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