- Thu May 28, 2020 12:23 am
#43194
noisymime wrote: ↑Sun May 24, 2020 10:44 pmA straight open-collector pulse from the UAF2115 chip on the back of my cluster (from a 1993 Volvo 240) into the flex input with the onboard 2.49k pullup to 5v resulted in some wild fluctuations in speed at idle. It would jump randomly from 3-15kph, and increase proportionally while driving. I once saw 400kph! The filtering/smoothing didn't work, but I don't know if that's due to the signal I was using or a firmware issue.Broke4speed wrote: ↑Sun May 24, 2020 1:37 pm Am I correct in assuming that this can only be used if VR2 is open?You can use the secondary trigger input (if not otherwise used) or any of the other 'interrupt enabled' inputs. If you've got one of the newer boards with an Ethanol/Flex input broken out, that works well.
The signal was perfect with a 330 ohm pullup to 12v on top of the onboard 2.49k ohm pullup to 5v, but that voltage would have killed my ecu pretty fast I bet .