The generator matrix

 1  0  1  1  1 14  1  1 12  1  1  2  1  1  8  1  6  1  1  1  4  1 10  1  1  0  1  1  6  1  1  1  0  1  6  1  1  1  8  1  2  1  1 10  4  1  1  4  4  1 10 10  2  6  0 12  4 12 14  1  6 10  2  1  1 10  1  1  2  1  1  1 14  6  6  2  1  1  1  1
 0  1 11  6  5  1 11 12  1  9  2  1  7  8  1  6  1  5  7  4  1 10  1  9  8  1 13 14  1  1  3  4  1 15  1  6  0  1  1 10  1  5  8  1  1  8  2  1  1 10  1  1  4  1  1  1  1  1  1  5  1  1  0  4 15  1 14  6 10  4 12  2  1  1  1  6  9  3 15 15
 0  0 12  0  0  0  0  8  8  8  8  8  8  4  4 12 12  4  4 12 12  4  4 12  0  4 12  4  8  8  0  8  8 12 12  0 12  4 12 12  0  8  8  0  4 12  0  4  8  8  4 12 12  8 12  8  0  4  8  0  4  0 12 12 12 12  0  8  4  8  0 12  4 12  4 12 12  4  0  0
 0  0  0 12  8  4  4  8  8  0  4 12 12  0  8  4  4  4  8  8  0 12 12 12  4 12  8  8  8  4  0 12  4  4  8  0 12  4  0  0  4  0  8  0  4  4  8  8 12  0  0  0  4  0  4  0  8 12 12 12  8  8  4 12  0 12  4  4  4  4  4  4  0  0 12 12  0  8  0  8

generates a code of length 80 over Z16 who´s minimum homogenous weight is 76.

Homogenous weight enumerator: w(x)=1x^0+613x^76+248x^77+616x^78+256x^79+713x^80+336x^81+592x^82+128x^83+428x^84+56x^85+72x^86+27x^88+3x^92+1x^96+1x^104+4x^108+1x^112

The gray image is a code over GF(2) with n=640, k=12 and d=304.
This code was found by Heurico 1.16 in 48.6 seconds.