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// Demux packets from a fifo based on the contents of the first line
// If first line matches the parameter and mask, send to data1, otherwise send to data0
module fifo36_demux
#(parameter match_data = 0,
parameter match_mask = 0)
(input clk, input reset, input clear,
input [35:0] data_i, input src_rdy_i, output dst_rdy_o,
output [35:0] data0_o, output src0_rdy_o, input dst0_rdy_i,
output [35:0] data1_o, output src1_rdy_o, input dst1_rdy_i);
localparam DMX_IDLE = 0;
localparam DMX_DATA0 = 1;
localparam DMX_DATA1 = 2;
reg [1:0] state;
wire match = |( (data_i ^ match_data) & match_mask );
wire eof = data_i[33];
always @(posedge clk)
if(reset | clear)
state <= DMX_IDLE;
else
case(state)
DMX_IDLE :
if(src_rdy_i)
if(match)
state <= DMX_DATA1;
else
state <= DMX_DATA0;
DMX_DATA0 :
if(src_rdy_i & dst0_rdy_i & eof)
state <= DMX_IDLE;
DMX_DATA1 :
if(src_rdy_i & dst1_rdy_i & eof)
state <= DMX_IDLE;
default :
state <= DMX_IDLE;
endcase // case (state)
assign dst_rdy_o = (state==DMX_IDLE) ? 0 : (state==DMX_DATA0) ? dst0_rdy_i : dst1_rdy_i;
assign src0_rdy_o = (state==DMX_DATA0) ? src_rdy_i : 0;
assign src1_rdy_o = (state==DMX_DATA1) ? src_rdy_i : 0;
assign data0_o = data_i;
assign data1_o = data_i;
endmodule // fifo36_demux
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