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Line 38... |
//
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//
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////////////////////////////////////////////////////////////////////////////////
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////////////////////////////////////////////////////////////////////////////////
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//
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//
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//
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//
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module addepad(i_clk, i_ce, i_en, i_cancel, i_v, i_d, o_v, o_d);
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module addepad(i_clk, i_ce, i_en, i_cancel, i_v, i_d, o_v, o_d);
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parameter MINNIBBLES=120;
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localparam LGNCOUNT=(MINNIBBLES<63)? 6
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:((MINNIBBLES<127)? 7:((MINNIBBLES<255)? 8:9));
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input i_clk, i_ce, i_en, i_cancel;
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input i_clk, i_ce, i_en, i_cancel;
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input i_v; // Valid
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input i_v; // Valid
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input [3:0] i_d; // Data nibble
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input [3:0] i_d; // Data nibble
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output reg o_v;
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output reg o_v;
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output reg [3:0] o_d;
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output reg [3:0] o_d;
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// 60 bytes translates to 120 nibbles, so let's keep track of our
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reg [(LGNCOUNT-1):0] r_ncnt;
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// minimum number of nibbles to transmit
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reg [119:0] r_v;
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initial r_v = 120'hff_ffff_ffff_ffff_ffff_ffff_ffff_ffff;
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initial o_v = 1'b0;
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initial o_v = 1'b0;
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always @(posedge i_clk)
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always @(posedge i_clk)
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if (i_ce)
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if (i_ce)
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begin
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begin
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if (((!i_v)&&(!o_v))||(i_cancel))
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if (((!i_v)&&(!o_v))||(i_cancel))
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begin
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begin
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r_v <= 120'hff_ffff_ffff_ffff_ffff_ffff_ffff_ffff;
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r_ncnt <= 0;
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o_v <= 1'b0;
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o_v <= 1'b0;
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end else if (i_v)
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end else if (i_v)
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begin
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begin
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o_v <= i_v;
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o_v <= i_v;
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r_v <= { r_v[118:0], 1'b0 };
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r_ncnt <= (r_ncnt<MINNIBBLES) ? r_ncnt+1'b1 : r_ncnt;
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end else begin
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end else begin
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o_v <= r_v[119];
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o_v <= (r_ncnt<MINNIBBLES);
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r_v <= { r_v[118:0], 1'b0 };
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r_ncnt <= (r_ncnt<MINNIBBLES) ? r_ncnt+1'b1 : r_ncnt;
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end
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end
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if (i_v)
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if (i_v)
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o_d <= i_d;
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o_d <= i_d;
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else
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else
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