The generator matrix

 1  0  1  1  1  1  1  1  1  0  1  1  1  0  1  1  1  1  1  2  1  1 2a  1  1  1  1  1  0  1  1 2a  1  1  1  1 2a+2  1  1  1 2a+2  1  1  1  1  1  1 2a  2 2a  1  1  1  1  1  2  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  1  1  a 3a+3  0 2a+3 a+1  a  1  0 2a+3  a  1 a+1  2 a+1 a+2 2a+3  1 a+1  a  1  0 3a a+3 2a+3 2a+1  1 2a+2 2a+1  1 a+2  0 a+3 2a+1  1 3a 2a+1 2a+1  1 3a+1 3a+3  3 2a+2 3a+1 3a+1  1  1  1  3 a+3 2a+3 2a a+3  1  1 a+2 a+2 2a+1 a+1  0 2a+1 2a 3a+3 3a+1  1 2a 2a+3 2a+3 a+3  a 3a+2 a+2 a+1  0 3a 2a  0
 0  0 2a+2  0  0  0  2  2  2  2  2  2 2a+2 2a+2 2a  2 2a 2a+2 2a+2  0 2a+2 2a+2 2a 2a+2 2a  0 2a  2  2 2a+2 2a 2a+2  0 2a+2 2a  0 2a 2a  2 2a 2a+2 2a+2  2  2  2 2a+2  2  2  0  2 2a 2a 2a 2a 2a 2a+2  0 2a  2 2a+2 2a  2  0 2a  0 2a 2a+2  0 2a+2 2a+2  2  0 2a 2a+2  0  2 2a  2  0
 0  0  0  2  0  2 2a+2  0  2 2a+2  2  0 2a 2a+2  0 2a+2  0  0 2a 2a  2  2 2a+2 2a+2  0 2a 2a  0 2a+2  2  2 2a  2  2  0  2 2a+2  2  0  2  2 2a 2a  2  0 2a+2  2 2a 2a  0 2a 2a  0  2 2a+2 2a 2a 2a+2 2a  0 2a  0  2 2a  0  2 2a+2  0  2 2a 2a  0 2a+2 2a+2  2  2 2a 2a+2  0
 0  0  0  0 2a+2 2a+2  2 2a+2 2a  0 2a+2  2  2 2a  2 2a 2a  2 2a+2 2a+2  0 2a+2 2a+2  2  0 2a+2  0 2a+2 2a+2 2a  2  2 2a  2 2a+2  2  0 2a 2a  0 2a  0  2  2 2a 2a 2a+2  2  0  0 2a 2a 2a  2  0 2a  2 2a+2  2 2a 2a+2  0 2a  0 2a 2a 2a+2 2a+2  0  0 2a  2  2  2  0  2 2a  0  2

generates a code of length 79 over GR(16,4) who´s minimum homogenous weight is 220.

Homogenous weight enumerator: w(x)=1x^0+60x^220+240x^223+507x^224+300x^226+684x^227+981x^228+456x^230+864x^231+1155x^232+552x^234+1260x^235+1341x^236+624x^238+1152x^239+1188x^240+732x^242+1140x^243+960x^244+360x^246+624x^247+729x^248+48x^250+180x^251+87x^252+57x^256+39x^260+15x^264+18x^268+9x^272+6x^276+3x^280+12x^284

The gray image is a code over GF(4) with n=316, k=7 and d=220.
This code was found by Heurico 1.16 in 1.83 seconds.