ultra cheap gauge to display any ECU parameter

[acannell]

Oh well if it's below $100 then take my money and build whatever you want. At that price i'm already sold and it doesn't even exist yet.

lol!

btw I found what may be a perfect display if something multi-line/graphical needs to happen. It should fit into the DTGAUGE housing as-is and is nice and big. Plus fairly cheap! Plenty of resolution, transflective, FSTN, and built in backlight. That big cable/flex pcb folds right below the glass so its not as big as the picture makes it seem.

Adding that to the mix would make for a GNARLY mega-gauge. Really I dont think it could get any crazier unless you added a keyboard jack and freaking started typing stuff into the gauge. I think this sort of display would only be justified if somehow a more complex user interface was needed. Personally I would not want to look at this display, even though its awesome, versus a bright, high contrast, 7 seg LED display, for critical engine parameters I'm actually watching while driving.

http://www.digikey.com/scripts/DkSea...30230498587322

[acannell]

Update:

I have now successfully arranged things so MPSCAN can query an external device for its inputs.

In this case, the external device is a thermocouple connected to my dual thermocouple gauge.

As you can see in the video, MPSCAN shows the live thermocouple temperature being read from the dual thermocouple gauge.

And the gauge also shows the temperature.

The way this works is as follows:

The microcontroller in the dual thermocouple gauge is intercepting all serial traffic between MPSCAN and the Chrysler ECU.

Normally it is just a pass-through, shuttling whatever data it sees between the two. So in that case MPSCAN and the ECU have no idea their data stream is being interrupted and retransmitted.

Now for MPSCAN to read the thermocouple, something special happens.

When the dual thermocouple gauge microcontroller sees MPSCAN request a specific ram location, in this case, 0xAD (SparkScatter), the microcontroller does not pass that command along to the ECU. Instead it responds immediately to MPSCAN with the current value of its thermocouple.

And in MPSCAN, I have made some cosmetic changes so the gauge shows up in degrees F and has a certain name.

The idea here would be to pick several ram locations in MPSCAN which are not used by anything or have data nobody cares about, and set them aside for being external inputs.

And so this is how we can have external things like thermocouples, pressure sensors, wideband AFR, all being logged in one place, MPSCAN. No more syncing up and now you can have your intercooler/plenum air, differential pressure, AFR, whatever, all being logged by MPSCAN.

At this point I am very close to deciding to run a first version of a circuit board, because the extra circuitry is cumbersome all wired up and floating about and doesnt have everything I want in it anyways. But there should be enough space on the existing DTGAUGE PCB to fit whatever is needed as far as this functionality, once the DAC gets deleted (not needed since analog outputs are for logging and now we can just log digitized serial data).

The bluetooth module will probably end up glued/epoxied in place in/on the housing some how, with 4 or 5 wires going to it. Its too big to fit on any of the existing PCB's.

You might notice the temperature in MPSCAN rolls-over to 0 when it goes above 255F. In the code its a float but i just have it dump it out as a byte so it rolls over in the dual thermocouple micro. But I'll fix that of course, no biggee. I think the way to do it would be to have mpscan expect 2 bytes for the temperature and in that way we could have nice resolution and a much higher maximum temperature, probably well beyond thermocouple melting temperature lol.


VIDEO HERE!

http://www.vid.me/7kS5

[DoubleD]

This is really sweet!

More random thinking over the weekend,
With the current display and PCB, Do you have a way to flash the display? To make it easier to see while driving, maybe the gauge could flash on and off as a warning if you exceed a value. Not sure if it's possible, but a nice safety feature none the less.
On the talk of price, I could see this gague also replacing the need for a boost gauge, with proper scaling, this gauge could show you your current MAP reading, the exact reading the engine ECU is seeing, no more need to run another vaccuum line into the car and one less gauge. Just my $.02

Also, do we really need a custom chrysler sci connector cable on the back of the gauge, why couldn't we just have the usb cable, it would cut costs not designing and manufacturing a special connector, Ideally most people who use this gauge are probably going to or are already using MPScan and MPTune, I know I will.

[acannell]

This is really sweet!

More random thinking over the weekend,
With the current display and PCB, Do you have a way to flash the display? To make it easier to see while driving, maybe the gauge could flash on and off as a warning if you exceed a value. Not sure if it's possible, but a nice safety feature none the less.
On the talk of price, I could see this gague also replacing the need for a boost gauge, with proper scaling, this gauge could show you your current MAP reading, the exact reading the engine ECU is seeing, no more need to run another vaccuum line into the car and one less gauge. Just my $.02

Also, do we really need a custom chrysler sci connector cable on the back of the gauge, why couldn't we just have the usb cable, it would cut costs not designing and manufacturing a special connector, Ideally most people who use this gauge are probably going to or are already using MPScan and MPTune, I know I will.

Yes the display can be flashed. I could also add a relay output to go to a buzzer and/or bright shift-style light.

There has to be at least one custom SCI cable with this product because it has to connect to the ECU. Unless it gets spliced in and isn't plug-in.

The other side of the connect, I'd like to keep as the chrysler SCI style, so that people can plug in whatever they want, be it MPSCAN, an OTC 2000, etc..

I suppose you could just cut your existing SCI jack off and re-splice it onto just a pigtail from this gauge. Its a possibility to save money!

[iangoround]

This sounds totally awesome and I want one.

[Moparbishi]

so... where do i send money and how much?

[acannell]

so... where do i send money and how much?

this is on a short list of projects I'd really like to work on...but at the moment this one is taking my attention:

http://www.turbododge.com/forums/f32...lve-2-2-a.html

[Moparbishi]

Another one I want to throw money at you for

[Moparbishi]

any updates?