Using internal counters on K8061

Hi,

I have been using a K8055 for a tachometer application, but I find that the pulse frequency is just a bit to high for it at times. I have purchased a K8061 card that should be able to cope with the higher frequencies (4kHz), but can find no mention of the internal 16-bit counters, as used on the k8055. How can counting tacho pulses be implemented on the K8061?

Kind regards,

John Orme