Hi, Atomski

I currently use the following lines for that

PULSIN , input,1, highpart
RCTIME , input,0, lowpart

PULSE = Highpart + lowpart + offset

( offset is time between falling edge of PULSIN and RCtime measurement beginning )

... and I measured offset to be 4 units ( !) at 20 Mhz and 0 at 4 Mhz

But note you lose the following pulse each time ( PULSIN has always to wait for the next rising edge ...)

Alain