Computer Fan RPM Sensor Reading

[markspend01]

Hey Guys well i think that nice info about computer fan Rpm sensor.Thanks!!

[CuriousOne]

I'd like to control rotation of PC fan (whenever it is rotating or not), but do not want to constantly call PULSIN. Is there some way of timer/interrupt combo, to do this in background?

[CuriousOne]

Found a special chip from Microchip for exactly that task - TC670: http://www.farnell.com/datasheets/87877.pdf

[CuriousOne]

Maxim also has almost similar chip - MAX6684, which is a bit expensive, but much simpler to use and no programming required.