If I had to do it over again, I probably would have done it differently.
But here's the (close to) end result of my gauge build- it uses an arduino mega, mcp2515 spi -> canbus transceiver, adafruit oled screen and neopixel ring. I've got a few more touches to put on it - like creating a 3rd and 4th menu (in the video you can see I scroll through my placeholders). I originally wanted an "at a glance" gauge to see if my oil was up to temp before I started flogging it, or something more visually distracting if I was beginning to overheat. I added the scrolling histogram for ***** and giggles (I have this feature in my PLX Gauge - but I don't use it much).
I've still got a list of todo's - some easy, some difficult
-- vital warnings - if, say, oil pressure is < 20psi at > 2000rpm, or coolant temp is ever > 230 degrees, automatically change gauge to display that value.
-- outer ring shift light - if TPS > 90% and RPM > 7000, turn the entire ring into a shift light
-- wire PLX sensors to megasquirt (they have a 0-5v reference that I can datalog), assign LED's to EGT, Oil pressure, Oil Temp
-- have a go at reading the LC-1 serial stream and writing that to megasquirt; no more ground offset worries (basically doing what JB has done with his canbus IO extender). If this goes together reasonably smooth, I might have a go with trying to capture the PLX gauges stream as well. I'm waiting on some parts right now, will probably try and get this working around christmas.
I'm also (attempting) to document this, afaik
I'm the first to get a non-native canbus speaking microcontroller (I looked at https://code.google.com/p/ms-can-dis...AN128.pde?r=56
a lot) to talk with a megasquirt. But I keep adding features and that keeps pushing the documentation back...
At the risk of begging for scope creep - what other functions you think would be cool to add to something like this?