  We analyze the memory capacity of a delay based reservoir computer with a
Hopf normal form as nonlinearity and numerically compute the linear as well as
the higher order recall capabilities. A possible physical realisation could be
a laser with external cavity, for which the information is fed via electrical
injection. A task independent quantification of the computational capability of
the reservoir system is done via a complete orthonormal set of basis functions.
Our results suggest that even for constant readout dimension the total memory
capacity is dependent on the ratio between the information input period, also
called the clock cycle, and the time delay in the system. Optimal performance
is found for a time delay about 1.6 times the clock cycle
