R = 2;
L = 8e-3;
Ka = 0.2;
J = 1e-3;
g = 5;

%

A = [-R/L, -(g+Ka)/L; Ka/J, 0];
B = [g/L; 0];
C = [0, 1; 0, -g];
D = [0; g];

%

sys = ss(A, B, C, D);

%

opts = stepDataOptions("stepAmplitude", 10);
step(sys, opts)