MPGuino release one workspace

[awillard69]

DBA: I wouldn't need it for any in-car testing, just designing the 555 circuit to provide bench top inputs instead of having to drive around.

If you would be willing to loan one for a while, PM me.

[silverknight]

Originally Posted by larrydag

Welcome aboard silverknight. dcb is leading the efforts. Read through the forums from the start. Look at this thread for build instructions (MPGuino release one workspace). For history of the project you can look through the "Any interest in developing an open source..." thread

As far as skills needed for the project:
1. Basic soldering
2. Installing software to Windows or Linux (for arduino)
3. Some car electronics knowledge to hookup power, VSS signal, Injector signal. Google should be your friend there. It was for me.

Thanks for the advice guys.

I need to get a paycheck then I can start buying parts. I am pretty good at soldering, computers (I am a web developer/programmer), and cars with some experience with car electronics.

I look forward to start planning and building.
Thanks,

[MetroMPG]

I've got the LCD wired up & attached to my mpguino. I don't have my USB cable with me at the moment though, so can't test it until tomorrow.

[dcb]

re: metro Unless you have some better values, try these:

#define vssPulsesPerMile 16408ul  
#define microSecondsPerGallon 535714286ul //injector flow rate

And these might help:




(need a wiki for this stuff)

[AndrewJ]

dcb: any advice on figuring out VSS or injector values for other motors? I have no clue what I'm doing...

Found out that my car (as well as any VX or CRX HF) has 190cc injectors. No idea how to convert that to microseconds per gallon.

With the VSS I guess I could just trial-and-error it against my odo.

*EDIT*

Later that evening....

So I found mosiers post way back on page 2 or 3, and did a little googling.

with the 190cc injectors I should have about 1249.8 seconds/gallon, so that's approximately
4999200000 uS

[dcb]

The easiest way is to drive at a known speed, take a guess at your mpg and look at the instant raw data, then "do the math" as they say. Jot down the numbers and take it to the bench.

Lets do the easy one first:
So lets say you saw VC=20 at 30mph with the 1/2 second refresh rate, well that would be 40 tics/second or 144000 tics per hour. So divide by 30mph and you have 4800 tics/mile.

Injector is a little trickier, not exactly sure how to explain it but anyway:
Lets say you guessed 40mpg at the 30mph. The injector uS said 20000. So if you drove like that for an hour, how much gas would you burn? 30/40 gallons? I cannot properly describe the conversion at the moment.


Only the testers will have to suffer this though, I hope we will have a wiki or other tool and possibly an online calculator to help folks just look up the values for their car. I would also like a "quick and dirty" setup mode in the guino at some point.

Also, I would like to explain better any discrepencies in computed from injector flow rate values and real world values at some point.

[mosier]

Originally Posted by AndrewJ

So I found mosiers post way back on page 2 or 3, and did a little googling.

with the 190cc injectors I should have about 1249.8 seconds/gallon, so that's approximately
4999200000 uS

It was pointed out that some of these injector ratings are at 80% duty cycle, which will throw us off quite a bit..

Anyway, you actually need to divide the 1250 sec/gal by 4 (1250 seconds to flow one gallon through one injector, 312 sec when using 4) This still isn't a proven way of determining the constant, but right now it seems worth a try..

Also check this post http://ecomodder.com/forum/showpost....&postcount=105
for what I think is a way to get an idea of what uS you would expect to see when at a steady state cruise (if you have a decent idea of what your mpg should be at that cruise speed)

I haven't checked my injector for power when key on, so I haven't made any progress in solving my low uS problem.

[MilesPerTank]

AndrewJ / Anyone with a Honda

http://www.b18c5eg.com/injectors.htm

the stock cx engine code is the d15b8 , 180CC. This reference may be wrong but we should cross compare. I'm also curious where you tapped for the injector/vss. I'm currently finishing up the circuit and havnt really felt the "urge" to go digging through the wiring harnesses.



I ordered the freeduino from NKC Electronics. It was probably the best shipping speed I have ever encountered from online sales (amazon, newegg, tire rack, etc..). When assembling it last night i noticed C8 is an electrolytic cap and while using the serial port it will be reverse biased (aka the positive end is the wrong way). When its not hooked up to the PC, it will be correctly biased (which it will be in this condition I hope all the time). So is it going to burn the house down and blow acid out the top? I dont know. I'm going to replace it with a ceramic/bipolar capacitor. Might be something you want to look out for.

[larrydag]

Great injector reference source MilesPerTank. So far the Honda owners that are doing the Opengauge project are myself, AndrewJ, and you.

As far as getting the INJ/VSS signal source I'm still working on that. AndrewJ has said that going directly to the Injector itself has worked. He and I both tried tapping into the ECU connector wire but we didn't have luck with that. I'm going to follow AndrewJ's method as well.

I still haven't worked out the VSS yet. Right now I'm hooked up with the ECU wire but I don't know if its worked correctly since my Injector signal doesn't work yet. AndrewJ seems to have it working with the ECU wire. He and I both posted pretty good ECU pinouts on this thread if you need that as a reference.

As far as the C8 reference that's beyond my knowledge. But I have the USB and serial freeduino's from NKC and they have both worked fine.

[awillard69]

DCB: It may be better for the long term if you create an include file with the user specific settings and include it into the main module. That way, if someone does the copy/paste of the core source, it won't overwrite their custom settings.

It might be useful, too, if settings for known auto (Saturn, Honda, etc.) configurations were surrounded in #define/#ifdef statements (if supported) in the file, so it can contain all collected defaults. Worst case, just uncomment the active settings. With the basic defaults being what a user may have tweaked. Then just a simple #define in the source can configure the code without losing the settings.