MAKE: Blog: AVR based RPM meter for cars

AVR based RPM meter for cars

Proto
Here's a cool AVR based RPM meter for cars, Bitman writes -

I got an idea of making a digital RPM-meter for my car. First I made a filter and used to test my code with a dev-board.

Pulse comes straight for cars rpm-meter.

CAR: Honda Civic 1988 Dual Carburetor
MCU: Mega32

The layout is a bit messy, but I think the pcb will tell the rest.

The filters main part is 7414 cause it has a Schmitt Trigger to make almost any kind of pulse to square wave.

Code uses interrupt to count the rising edges of the pulse in a time unit, which is around one second.

:: AVR Freaks - Link.

Related:

Comments

Oldest comments listed first.

Posted by: zedomax on April 30, 2007 at 3:55 PM

Hey, Phil,
I can't get into the link unless you are a member...

Posted by: philliptorrone on April 30, 2007 at 4:01 PM

i registered, it was ez

Posted by: kaek on May 11, 2007 at 3:53 AM

A meter for revolutions per minute is typically called a tachometer. Just bein' persnickety, but jeez man, its a tach, not a "novel contraption for deducing the revolutionary moments of a spinning axle performing useful work."

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