The generator matrix

 1  0  1  1  1  6  1  1  0  1  1  6  1  1  6  1  1  0  1  0  1  1  6  1  1  1  0  1  1  1  4  1  6  1  1  1  1  1  1  1  6  1  0  2  1  1  1  1  2  1  1  1  1  6  6  6  1  1  1  1  1  1  2  4
 0  1  3  6  1  1  0  3  1  6  5  1  0  3  1  6  5  1  5  1  6  3  1  0  0  3  1  6  5  1  1  0  1  2  7  5  4  6  5  0  1  3  1  1  5  4  3  7  1  7  4  6  5  1  1  1  3  4  2  5  3  3  4  0
 0  0  4  0  0  0  0  0  0  0  0  4  0  4  4  4  4  4  0  4  4  0  4  4  0  4  0  4  0  4  4  0  0  0  4  0  4  4  0  0  0  0  4  0  4  4  0  4  4  4  0  4  4  4  0  4  4  4  0  4  0  0  0  4
 0  0  0  4  0  0  0  0  0  4  0  4  4  0  4  0  4  0  4  0  4  4  4  4  4  4  0  4  0  4  0  4  4  4  0  4  4  0  0  0  0  0  4  0  0  0  0  4  0  0  4  4  0  0  4  0  4  0  4  4  0  0  4  4
 0  0  0  0  4  0  0  0  0  4  4  0  4  4  0  0  4  4  4  4  0  0  4  4  4  4  4  0  4  4  0  0  4  4  4  0  0  4  4  0  0  4  0  0  0  0  4  0  0  4  0  0  0  0  4  0  0  0  4  0  4  0  4  0
 0  0  0  0  0  4  0  0  4  0  4  4  0  0  4  4  4  0  0  4  4  4  0  4  0  0  0  0  4  4  0  0  4  4  4  4  4  0  0  4  0  4  0  0  4  4  0  0  0  4  4  0  0  4  4  0  0  0  0  4  4  0  4  4
 0  0  0  0  0  0  4  0  4  0  0  0  4  0  4  0  4  4  4  4  4  4  4  0  0  0  0  4  4  0  4  4  4  0  4  0  0  4  4  4  4  0  4  0  0  4  4  0  0  0  0  4  4  0  0  0  0  4  4  4  0  4  0  0
 0  0  0  0  0  0  0  4  4  0  4  0  0  4  4  4  4  0  4  0  4  0  4  4  4  0  4  0  0  0  4  4  4  4  4  4  0  0  0  0  0  0  0  4  4  0  4  4  0  4  4  4  4  0  0  4  0  4  4  4  4  4  4  0

generates a code of length 64 over Z8 who´s minimum homogenous weight is 56.

Homogenous weight enumerator: w(x)=1x^0+93x^56+40x^57+216x^58+100x^59+502x^60+164x^61+474x^62+212x^63+550x^64+196x^65+522x^66+172x^67+383x^68+108x^69+190x^70+28x^71+108x^72+4x^73+6x^74+14x^76+5x^80+5x^84+3x^88

The gray image is a code over GF(2) with n=256, k=12 and d=112.
This code was found by Heurico 1.16 in 0.812 seconds.