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//
// Copyright 2014 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: LGPL-3.0-or-later
//
module axi_fifo64_to_fifo32
(input clk, input reset, input clear,
input [63:0] i_tdata, input [2:0] i_tuser, input i_tlast, input i_tvalid, output i_tready,
output [31:0] o_tdata, output [1:0] o_tuser, output o_tlast, output o_tvalid, input o_tready
);
wire short_last = i_tlast & ((i_tuser == 3'd1) | (i_tuser == 3'd2) | (i_tuser == 3'd3) | (i_tuser == 3'd4));
reg state;
always @(posedge clk)
if(reset | clear)
state <= 1'b0;
else
if(i_tvalid & o_tready)
case(state)
1'b0 :
if(~short_last)
state <= 1'b1;
1'b1 :
state <= 1'b0;
endcase // case (state)
assign o_tdata = (state == 0) ? i_tdata[63:32] : i_tdata[31:0];
assign o_tuser = o_tlast ? i_tuser[1:0] : 2'd0;
assign o_tlast = i_tlast & ((state == 1'b1) | short_last);
assign o_tvalid = i_tvalid;
assign i_tready = o_tready & ((state == 1'b1) | short_last);
endmodule // axi_fifo64_to_fifo32
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