Getting TPS and RPM into Harry's LapTimer without OBD2

timk · Postby **timk** » Tue Jul 03, 2012 9:39 pm

Hey guys,

I've been thinking of starting a project using either an Arduino with WiFi or a Raspberry Pi with a USB WiFi dongle.

Both these devices have GPIO pins, but it looks like the Raspberry Pi lacks analog inputs so it may not a good choice.

The plan is to convert the TPS voltage and the RPM pulses into digital signals, and emulate an ELM327 presented via WiFi.

Harry's LapTimer should then be able to grab data from it.

Very early stages, just seeing what you guys think?

Cheers

plohl · Postby **plohl** » Fri Jul 06, 2012 1:07 am

That would be well cool

Zcootz · Postby **Zcootz** » Sat Jul 14, 2012 10:39 pm

Have you looked at the Pic processors ? They have A/D converters built in. I knocked up a shift light for my rally car with a Pic and worked out the revs by timing the spark, a friend wanted one for a Wrx which was much easier as it had a nice 5v clean tacho drive signal to work from. Hopefully the mx5 has a simar signal.

The Rasberry PI may be a problem with supplies, I've been told I've got to wait another 6 weeks for mine and that they are only shipping one off's due to a policy to widen the distribution.