It's a weather station - and I'm measuring wind speed using an anemometer.

The anemometer counts the pulses that occur in 3.6 seconds and this gives the wind speed in kph.

I want to do this 'in the background' whilst the MCU gets on with other tasks.

I am already using an ASM interrupt 'INT0' to count 'bucket-tips' for rainfall as a background process.

The station runs on a PIC18F8722 mcu.

Any advice/ideas on making the count a background process?

Regards Bill Legge