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// ============================================================================
//        __
//   \\__/ o\    (C) 2020  Robert Finch, Waterloo
//    \  __ /    All rights reserved.
//     \/_//     robfinch<remove>@finitron.ca
//       ||
//
//      DPDEncode.sv
//
// An encoding described in:
//      Densely Packed Decimal Encoding, by Mike Cowlishaw, in 
//
// See: http://speleotrove.com/decimal/DPDecimal.html
//
// BSD 3-Clause License
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// modification, are permitted provided that the following conditions are met:
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//                                                                          
// ============================================================================

module DPDEncode(i, o);
input [11:0] i;
output [9:0] o;

wire a,b,c,d,e,f,g,h,ii,j,k,m;
wire p,q,r,s,t,u,v,w,x,y;

assign {a,b,c,d,e,f,g,h,ii,j,k,m} = i;

assign p = b | (a & j) | (a & f & ii);
assign q = c | (a & k) | (a & g & ii);
assign r = d;
assign s = (f & (~a | ~ii)) | (~a & e & j) | (e & ii);
assign t = g  | (~a & e &k) | (a & ii);
assign u = h;
assign v = a | e | ii;
assign w = a | (e & ii) | (~e & j);
assign x = e | (a & ii) | (~a & k);
assign y = m;

assign o = {p,q,r,s,t,u,v,w,x,y};

endmodule

module DPDEncodeN(i, o);
parameter N=11;
input [N*12-1:0] i;
output [N*10-1:0] o;

genvar g;
generate begin : gDPDEncodeN
        for (g = 0; g < N; g = g + 1)
                DPDEncode u1 (i[g*12+11:g*12],o[g*10+9:g*10]);
end
endgenerate

endmodule