MPGuino release one workspace

[rmccomiskie]

Yes. I have swapped FALLING/RISING to RISING/FALLING on the external interrupt pins. That solved the problem of GPH going up when stepping on the accelerator. I have not tried tapping the injector. I'll try that this weekend to confirm that the Fundamental Logic MPGuino is working properly.

Thanks for the info that the ECU flat line when coasting probably won't be handled correctly. At least I know I've got to dig deeper into the code. I'm beginning to get a feel for it.

I use a Scope program that I downloaded from the Web. And I capture images of the Scope display with Paint Shop Pro. That allows me to capture many successive images of just the display by just pressing the right mouse button.

I tapped between a couple of resistors (input-->100K--tap--10K-->ground) to drop the input signal down to a reasonable level for the laptop sound card input.

It works really well at the frequencies we're dealing with here. Try it. You'll like it.

Here's the URL: Oscilloscope for the Soundcard

[americasfuture2k]

lol messege, that was a typo

whoa, i just looked into that soundcard oscillicope, and that seems to be something very useful to me. one thing i couldnt find from some glancing around on google, its what is the max safe voltage to use? im paranoid about frying my laptop or my audigy sound card.

[dcb]

Originally Posted by rmccomiskie

Yes. I have swapped FALLING/RISING to RISING/FALLING on the external interrupt pins. That solved the problem of GPH going up when stepping on the accelerator....

Ok, please do try the injector tap, but you might have to undo the FALLING/RISING change, i.e. just use the standard codebase.

I think your pictures might be upside down? (based solely on the above comment).

[rmccomiskie]

Originally Posted by dcb

Ok, please do try the injector tap, but you might have to undo the FALLING/RISING change, i.e. just use the standard codebase.

I think your pictures might be upside down? (based solely on the above comment).

I'm running this code:

//  attachInterrupt(0, processInjOpen, FALLING);      //for positive going signal
//  attachInterrupt(1, processInjClosed, RISING);
  attachInterrupt(0, processInjOpen, RISING);      //for negative going signal
  attachInterrupt(1, processInjClosed, FALLING);

The signals are all relative to chassis ground so they should be right side up. I thought it odd that your original code was FALLING/RISING but I just reversed them and it works. I'll rig an injector tap this weekend and see how it behaves.

whoa, i just looked into that soundcard oscillicope, and that seems to be something very useful to me. one thing i couldnt find from some glancing around on google, its what is the max safe voltage to use? im paranoid about frying my laptop or my audigy sound card.

I've found that a max of 1.0-1.5V is safe. Since my car runs about 14V, when I use the 100K/10K resistors, the max voltage I'd expect at the sound card input is 1.27V. I've never had a problem with this setup.

If you're really paranoid, you could build this Buffer Hardware for xoscope to buffer the input and allow adjustability. I've got the parts. One of these days, in my free time, I'll get around to it.

[americasfuture2k]

what do i need to change to make the greeting message show up longer?

[dcb]

you should only see the greeting message when you first plug it in, so what is the deal?

[americasfuture2k]

since i changed the greeting, i would like it to stay on for about 2 or 3 seconds, whichever feels right when watching it.

[rmccomiskie]

I finally tapped the injector signal instead of the ECU signal. The MPGuino seems to be working normally. Importantly, when coasting, the GPH displays reasonable values, i.e. it drops to a very low rate as it should. I'll keep this setup for a while and dial in the uSec per gallon number.

So, my original complaint, that the GPH jumped to a very high rate when coasting, appears to be related to using the ECU signal for fuel flow and reversing the injector open/closed pins to handle the negative signal.

I'd still like to use the ECU signal. I know now that the MPGuino is working correctly and that I'll have to dig into the code to resolve the issues.

[yetimus]

Originally Posted by rmccomiskie

I'd still like to use the ECU signal. I know now that the MPGuino is working correctly and that I'll have to dig into the code to resolve the issues.

I'd be very interested to hear if you find a way to use the ECU fuel consumption signal. I'd like to adapt the MPGuino to a VW Passat TDI which has no injector signal available (it's a rotary pump injection system), but it does have an ECU fuel consumption signal similar to yours.

Good luck and keep us posted!

[dcb]

Originally Posted by yetimus

but it does have an ECU fuel consumption signal similar to yours.

Huh, well, hmm. Another possible option for the TDI's then.

Problem really is trying to figure out exactly what that audi signal means. if it could drive the interrupt, that would be best, but peak value might come into play where you have to integrate the entire pulse via polling or somesuch.