Question: Need to Solve System of ODE Using RK-4

Hello Everyone;

I need help to solve the following system using rk-4 method

restart;
NULL;
NULL;
C := 1.0;
gK := 36.0;
gNa := 120.0;
gL := 0.3;
VK := -77.0;
VNa := 50.0;
VL := -54.0;
III := 20;
alpha_n := 0.01*(v(t) + 55.0)/(1 - exp(-1.0/10.0*v(t) - 11.0/2.0));
beta_n := 0.125*exp((-v(t))/80.0 + (-1)*13.0/16.0);
alpha_m := 0.1*(v(t) + 40.0)/(1 - exp(-1.0/10.0*v(t) - 4.0));
beta_m := 4.0*exp(-1.0/18.0*v(t) - 65.0/18.0);
alpha_h := 0.07*exp((-1)*(v(t) + 65.0)/20.0);
beta_h := 1/(1.0 + exp((-v(t) + 35.0)/10.0));

dsys1 := {diff(h(t), t) = alpha_h*(1 - h(t)) - beta_h*h(t), diff(m(t), t) = alpha_m*(1 - m(t)) - beta_m*m(t), diff(n(t), t) = alpha_n*(1 - n(t)) - beta_n(t), diff(v(t), t) = III - gK*n(t)^4*(v(t) - VK) - gNa*m(t)^3*h(t)*(v(t) - VNa) - gL*(v(t) - VL), h(0) = 0.9996937394, m(0) = 0.02890553447, n(0) = 0.2445865495, v(0) = -70};