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Old 04-30-2017, 10:21 PM   #112 (permalink)
Join Date: Oct 2016
Location: Seattle, WA
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s2k - '02 Honda s2000
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Now, i want to build one for my motorcycle (Ninja 250 or Ninja 300 in US).
For this build, i want to use Arduino Nano v3 atmega328p + I2C serial interface for the LCD 16x2 or 20x4. Is it compatible with your version? I'm gonna build it based on schematic found in here:
I have Vago's code running on an Arduino Pro Mini 3.3v 8MHz, (Amazon $10 for 3 of them) and it runs well. I also have it running on a TinyDuino, $20 but the size of a quarter. The hard part for anything nonstandard is you may need to make the car-to-arduino interface yourself. It's not hard, just follow the online schematics. You'll need a 7805 12-to-5 volt regulator, two 50k (or 47k or 51k) resistors (or 100k). Also, do NOT power the LCD from the 5V pin on the arduino, you will fry the on-board regulator. For the LCD I recommend the Adafruit button-and-LCD shield, then you only need 2 wires between the arduino and the LCD unit.

You will want to base your design on this schematic instead of the one you're suggesting, since the on-board voltage regulator -- well, I'll just say I've fried many, many arduinos by not using a beefy 7805 regulator. I'm still trying to get around it, and your mileage may vary.

Remember: you can avoid the worst part of the wiring by using an LCD that already has it's own processing, such as the Adafruit one. (Check t-vagos code for all supported LCDs); as managing the wires between a small arduino and 12 pins of an LCD display is nasty. If you do go with the Adafruit LCD be sure to power it from the voltage regulator and not the arduino. Good luck!

The only reason I'm using the 3.3v 8MHz version is so that I can send serial output to a Pi, which will fry if it has 5v inbound on the receive pin, so you can certainly use the 5v arduino nano/pico/mini, etc. I suggest using a breadboard to get your car-to-arduino working before you solder.

Would be great if you could put your schematic in this thread to help others (like me) who wants to be build new one with the latest software but didn't know if your version is compatible with the schematic above or not
As far as I can tell by reverse-engineering t-vago has a series of test mules, but not a particular PCB design. T-vagos stuff works very well on the Meelis hardware if you want a nice, tight package, and I believe it would be trivial to change out the LCD in Meelis' hardware from a 16x2 to a larger display (20x4?); I have given up on LCDs, but IIRC there are many adaptations already using 4-line displays, so I'd assume t's code supports it as well.
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The Following 2 Users Say Thank You to skybolt For This Useful Post:
alvin_wj (05-01-2017), t vago (07-28-2017)