bobnova 59 Posted September 5, 2014 Share Posted September 5, 2014 Recently there was a contest for applications using TI's ESI hardware rotation/flow sensing peripheral, I was one of the winners of that. Actually TI did a pretty cool thing and gave the prize (target board and programmer) to everybody who entered rather than just their favorite five. Go TI! In any event, here is product pitch I submitted: Digital tachometer, speedometer, and intelligent shift light.Uses the ESI to read either the ignitor's tach output (one pulse per ignition event, so two per engine revolution) or the vehicle speed sensor's square wave (whichever is more difficult to do with interrupts/timers, unknown at this time) as well as the throttle position sensor.Displays engine RPM via either LCD screen or RGBLED bars (or both, plenty of GPIO here), also vehicle speed with LED indicators for common speed limits.Based on throttle position, engine RPM and vehicle speed (and gear, calculated via engine RPM and road speed) it will also have a pair of shift lights, one to indicate for downshifting and one to indicate for upshifting.Example: On the freeway behind someone at 60MPH in a 65 zone in 5th gear, left lane opens up and you can accelerate. If you give the engine a little bit of gas to accelerate slowly, no lights. Stomp on the gas and the downshift light comes on (perhaps blinking, to indicate multiple gears downward are indicated, as full throttle 60MPH is best done in 3rd gear on this car). If/when you downshift, the light goes out. Let off the throttle to maintain your new speed and the upshift light comes on, as 65MPH in 3rd is lousy for cruising.Also indicates upshifts based on engine RPM directly, given a 6750 redline and high throttle angle the upshift light would come on around 6500RPM.I may make the MCU learn the rev limits, may not.ESI and FRAM are not specifically needed for this project, but using ESI for either tach or road speed would eliminate timing artifacts that would happen if the road speed and tach signals happened simultaneously, something that is guaranteed to happen eventually. I also submitted a more advanced version that ties into the fuel injectors and computes instant and average mileage, but I may or may not get to that in a reasonable time period. This is my project thread for this project, if you hadn't guessed. I'll be updating this first post as progress continues, as well as making more posts in the thread. I welcome any/all input, feature ideas, suggestions, comments, etc. I'm hoping to begin work on prototype code later today, I'll probably start off using a MSP430G2553 rather than a FRAM w/ESI chip, as I'd much rather blow up a $2.70 chip than a $25 launchpad or a FRAM MCU that isn't available for sale yet. I do have a FR5969 launchpad, which has the ESI bits in it as well, that will go into use once I make sure the inputs are at the voltage(s) I think they are. spirilis and abecedarian 2 Quote Link to post Share on other sites
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