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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/>.
+//
+
+
+
+module ram_to_fifo
+ (input clk, input reset,
+ input [10:0] read_length, // From the dbsm (?)
+ output read_en, output reg [8:0] read_addr, input [31:0] read_data, input read_ready, output read_done,
+ output [35:0] data_o, output src_rdy_o, input dst_rdy_i);
+
+ // read_length/2 = number of 32 bit lines, numbered 0 through read_length/2-1
+ wire [8:0] last_line = (read_length[10:1]-1);
+
+ reg read_phase, sop;
+
+ assign read_en = (read_phase == 0) | dst_rdy_i;
+ assign src_rdy_o = (read_phase == 1);
+
+ always @(posedge clk)
+ if(reset)
+ begin
+ read_addr <= 0;
+ read_phase <= 0;
+ sop <= 1;
+ end
+ else
+ if(read_phase == 0)
+ begin
+ read_addr <= read_ready;
+ read_phase <= read_ready;
+ end
+ else if(dst_rdy_i)
+ begin
+ sop <= 0;
+ if(read_addr == last_line)
+ begin
+ read_addr <= 0;
+ read_phase <= 0;
+ end
+ else
+ read_addr <= read_addr + 1;
+ end
+
+ assign read_done = (read_phase == 1) & (read_addr == last_line) & dst_rdy_i;
+ wire eop = (read_addr == last_line);
+ assign data_o = { 2'b00, eop, sop, read_data };
+
+endmodule // ram_to_fifo