Nistune Forums

I am doing a small project to build a RPM Window Switch using Arduino, I have searched online and can not find the answer, but basically, I am looking to get details on how to Measure the RPM from the ECU.

I am unsure whether it uses voltages or digital signals or what, but basically I would like the Arduino to display the RPM on the display screen and Com Input so I can then build the rest of the code around it. If it is voltage or other signal is there any other conversion which would need done to build into the code to interpret the data?

Yes it is a voltage from the ECU. 5V pulse which frequency increases as RPMs increase

Matt wrote:Yes it is a voltage from the ECU. 5V pulse which frequency increases as RPMs increase

Thanks Matt, Would a ADC converter convert the values to a number so it can be displayed using an Arduino?

I once got this working on an Arduino using a 74HC14 (schmitt trigger) and frequency counter library or freqmeasure library...can't remember which one I used, but I think both worked.

No ... you need to count pulses in a time period to measure. Frequency counters or similar extra ICs like Eric mentioned can assist