The other retro display is the 7 segment incandecent. They can have a tint similar to nixies, but run on 5V. Have used a few here. Bruce Roe

Ah yes, The "Numitron" I had a tinker with them a while back too, a friend gave me some.

They're nice, a bit small, and not quite a pretty as a nixie, but still a very nice glow effect compared to an LED.. The only problem is, they use a huge (relatively for an electronic display anyway) amount of current to run for a bright glow, my Linear reg powering that gadget was getting toasty warm, even with a small heatsink.

If you like Retro display tech, the neo-nixie mailing list (on yahoogroups) has lots of discussions about nixies, numitrons, edge-lit, Dekatron, PixiTrons, Flip-Discs (the big clack-clack type displays commonly used in airport arrival/departure boards and just about every vitage display tech you can think of.. Fun reading.

Hey Brett,

First off, awesome implementation on your car mate, sure everyone's also commented how great it is, top banana mate!!

First up, apologies for the thread jack, I'lkl happily PM / email if it's better as a seperate question.

I actually want to go "the other" way with my overall install - ie make things a bit more "modern" than retro, so I suppose the best question I could ask is for info / links to arduino being used for tacho, speedo, MPG, fuel tank level, etc. Basically I'd like to replace the clocks I have in my VW with something a bit more bespoke, tied into MJLJ where necessary. I've seen graphing displays, etc for the arduino, but as I've NEVER used it (happy with the idea and programming behind it though) figured I'd ask the question.

Now I know that I can buy an off the shelf unit that'll do it all... but where's the fun in that right?

Cheers,
Rich

There are quite a few options for displays when you head into the open source world of arduino's.

One project that covers a lot of the functions you mention is the "MPGuino" - although most of them use the cheap and easily available 2 or 4 line character mode LCD's
http://www.google.com/search?q=mpguino

if you have more dollars to spend and you want funky graphics, then you can go for an OLED color bitmap display - good for sunlight readability
http://www.google.com/search?q=arduino+oled

Another option is to use the Arduino to drive Micro RC servo's (used in small electric RC planes etc), which you use to move a needle on a modified conventional analog gauge of whatever style/vintage you want. If you want more than 180 degrees of needle movement (speedo/tacho), then use "winch servo's". Most standard servo's can only move 120-180 degrees.

Yet another option is to use a portable computer device as your display unit with bluetooth or Wifi. eg an Android powered phone, or a hacked Iphone, or a Netbook. a bit tricker to make look nicely integrated into your dashboard, but easy and ready-to-roll.

Or, head on over to mp3car.com (which as you can guess from the name was originally about putting computer/MP3 players in cars (way back when that was a revolutionary idea) but is now a general car-computer website with everything from gps to voice command and has some very nice custom computer dashboard ideas.

There is an even an Ubuntu linux distribution that is customised for car-computer/virtual dashboard implementations.. cant recall the link right now though.. if you are interested in tinkering with linux dashboards, let me know and I'll find it.

It sounds the MPGuino is your best starting point though..

In my experience, the code/electronics behind the front-panel is the easy part.. you can hide all the circuit boards and wires out of sight.. but making the actual displays look "OEM" (Original Equipment Manufacturer - like it is supposed to be there and not grafted on with duct-tape and bluetack) is the hard part

Its easy to grab the Megajolt decoding part out of my code and leave the Nixie/LCD/I2C drive bits out to adapt it to a different display. If you need some pointers, ask away.. That will give you tacho, temp, vacuum (map), advance.. Reading other non-megajolt connected sensors like Fuel Tank levels, Speed sensors and so on will require some more code writing..

regards

Brett

Brett,

Many thanks dude... I have a hill to climb, but thankyou for the cramp-ons

I'll be in touch, lol. (like a fly at dinner time!!)

*edit* MPGuino is gonna be no good, unless I'm missing a trick - it's for injected cars of which mine aint.

Cheers,
Rich



Last edited by Funky Diver on Wed Jun 16, 2010 2:12 pm; edited 1 time in total

ah yes, I forgot the MPGuino picks up data from a FI computer.
Still, I mentioned it mainly as an example of automotive display use for an Arduino..

If you want to measure fuel/flow of a carb'ed car, you just need a fuel flow to pulse sensor - Swissflow make some nice fuel-rated ones.

Speed sensors can be bought from a number of places - look for digital speedo sensors - although they are expensive, if you want to do it on the cheap, bicycle computers can be had for less than $20 and you can use the sensor they come with to get started.

Speed/Distance and Fuel Flow sensors will give you what you need to do the MPG stuff..

What I havent found yet is a reasonably-priced (not $80-$100 each) fuel *pressure* sensor.. anyone know of one ?

TBH, in my car I'm not going to be wanting to view MPG else I'll never drive it, haha... BUT, speed and distance travelled as well as RPM would be pretty swish, along with fuel tank level. The kinda stuff you get on a standard set of clocks

And you've opened a right can of worms now, as you have effectively sorted out my "computing" requirements for my after market stalk solution

At least 2 arduino boards required now!!

In terms of power requirements, still looking through the specs tbh... does the arduino cope pretty well with vehicular power (presumably with the use of rectifiers n wotnot)

Well, the single board in my car has been humming along without a hiccup so far, and dealth with voltages from 10 to 15v. I have a diode followed up by an Electro Cap on the power input to stabilise things a bit and that seems to keep it happy

Sailesmarketing,com do some interesting adapters for speedos & there's 1 for The Acewell dashes too.

Interesting project, I hadn't thought of reading the data out of the MJ for Arduino based trickery. I was thinking of doing it the other way round via the auxiliary input to have a go at traction control (by retarding the ignition, rev limiter style, from 1 bin set off the scale of the actual aux/temperature range. This way looks potentially easier - as does turning analogue sensor data into a linear digital range with 'duino.

Funky, if you're running an electric fuel pump have you looked at whether you can get a signal out of that? You might also get lucky with original eqpt off an old "executive" car with a trip computer but no injection Rovers, Jags, Granadas.....

Ooooh, good idea...