RFC: Custom OBD-II datalogging software

[Matz]

Hi everyone, I'm posting up a request for comments regarding some software that I started working on for fun.

I scrapped what I have so far, because I thought it would be cool to write something using input that I get from you guys here that datalog often.

Basically, I'd like to get feedback about what you think are cool features in software you've used so far, as well as ideas / features that aren't present in those software packages.

All I've come up with so far are a few dialogs:
1. Graph view - plots data points for various parameters
2. Chart view - puts data into an Excel-like grid
3. Raw data - logs all data as it's read from the ECU
4. Notes - you can write notes here and it will be associated with a particular set of raw data.

And some random features:
1. Open multiple data files in a graph to superimpose plots
2. Read ECU error codes and clear them
3. Specify which parameters to read. This is important because the logging bandwidth is about 10Hz, so the more parameters you want to read, the less frequently each parameter will be updated.

Do you guys have any other cool ideas?

[earlyapex]

I've been looking into ECU+ alot lately and I think it's interface, logging and graphing looks pretty sweet:

http://www.ecuplus.com/winshot7-l.jpg

http://www.ecuplus.com/winshot.htm

[Matz]

Those screens look great, thanks! Mine will only offer a subset of that info, since I'm limited to whatever Mitsubishi reports over the OBD2 port. I don't know how fast I can write this, but if you're interested, I'd like to send you the executable to play with sometime. Who else here datalogs a lot?

[earlyapex]

Let me know when you have something for me to play with.

I currently log via pocketlogger so I only have an obd2 connection for that.

I do have a windows laptop, but no obd2 connector for it... yet.

[Matz]

Hey Bryan, if you're willing to test that for me, then don't buy an OBD2 connector. I was planning on buying an extra that I can loan out to the NCE guys along with the software. Then you can take it and play with it for a while, and give it to the next guy to play with. I'm using the VIA from B&B Electronics, and like it a lot. The only problem is that the box sticks out so far that it interferes with the driver's right foot. I need to get a right angle adapter or something.

This project is really just a stepping stone for the next project, which is to have datalogging in a car w/o the laptop, using the same OBD2 adapter that I have now. However, given the crappy datarates, don't you think it's more worthwhile to have a harness that taps the signals directly from the ECU instead? Just curious... clearly, the OBD2 approach will be easier. I could definitely get a board fabbed for the ECU approach, but as I'm not a true EE, I would probably make some errors with the circuit itself. :)

[300kpa]

I do a lot of datalogging with my UTEC, which logs RPM, boost, factory timing, my modified timing, injector duty cycle, MAF signal, modified MAF signal, knock events, modified fuel, etc. But with the speed of factory OBD port, you don't want to gather too much info. Info like RPM, Ignition timing, Long Term Trim, Short Term Trim, knock voltage and O2 reading are useful.

In reality, the O2 reading can only be a reference, so a WB should be used for real tuning. Long/short term trim data should only be needed to know how the ECU want to tune your close loop and idle. So that leaves 3 important info to be logged to speed things up, 1) RPM, 2) Ignition Timing, 3) Knock Voltage (you don't really need it, but it can be useful to see if the factory knock signal being overly sensitive and caused the timing to be retarded.

[earlyapex]

the inputs I log when tuning are:

1. RPM
2. TIMING
3. TPS
4. 02 bank 1 (just to see if the 02 readings stay constant, Wideband is better of course)

That's all you need from the OBD2 port when tuning with a pocketlogger.

I do monitor my short term and long term fuel trims every once and while as well, but never log them.

The direct ECU connection approach of course would be better since you wouldn't be limited to the obd2 port speed. This is what ECU+ uses.

I would be happy to test whatever you end up making.

[Matz]

anyone know where to get a harness that goes in between the stock harness and ECU? That way, I wouldn't have to tap into each line.

Thanks for the input, guys! Keep it coming!

[earlyapex]

RRE sells the harness, that's where I bought mine.

Other places sell them too, lancershop I think, and a couple others.

[Cameron@xperformance]

if you want to make a mac version, ill test for that :lol:

[Matz]

if you want to make a mac version, ill test for that :lol:

Thanks, Cameron. Although it's entirely possible to use a cross platform window framework to write the application, it may take longer than it already would if I just target Windows users. We'll see!

[Matz]

RRE sells the harness, that's where I bought mine.

Other places sell them too, lancershop I think, and a couple others.

Got a link to RRE's product page? I could only find the turbo timer harness. The ones from lancershop are damn expensive, though that's what I had expected...

Also, does anyone know what page number in the FSM has the pinout for the ECU? i.e. what signal is on what wire? I looked up Engine - ECU in the index, and it was pretty useless info.

[earlyapex]

You have to call RRE. They have alot of items that haven't made it to the product page yet.

[Matz]

You have to call RRE. They have alot of items that haven't made it to the product page yet.

Do you remember how much it was? If it's about the same as lancershop, I'll just order it from there since it's so easy. :) I'd get it from RRE if it's <= $100

[earlyapex]

here ya go, $50

http://www.fasterthanthem.com/buy/product.php?productid=2347&cat=0&page=1&featured

also:

http://www.boomslang.us/evo.htm

http://www.boomslang.us/extension.htm

[Matz]

here ya go, $50

http://www.fasterthanthem.com/buy/product.php?productid=2347&cat=0&page=1&featured

also:

http://www.boomslang.us/evo.htm

http://www.boomslang.us/extension.htm

You da man, thanks! I just ordered a couple of them. What a deal! Now all I gotta do is hope that I don't blow up my ECU. But I won't worry about that project until after I get the OBD2 project done. :)

[EFIxMR]

ECU+ looks pretty kool.

[earlyapex]

ECU+ looks pretty kool.

Yea I think I am going to be playing around with it soon. It looks like a SAFC and a XEDE had whoppie and spawned a offspring.

[Matz]

ECU+ looks pretty kool.

Yea I think I am going to be playing around with it soon. It looks like a SAFC and a XEDE had whoppie and spawned a offspring.

Yeah, ECU+ looks really nice. Too bad I don't know anything about tuning. Anyhow, I did get one harness from FasterThanThem yesterday, and it looks nice. I think it'll be really good for making a better datalogger than what can be done with the OBD-II port. I'm thinking that I should do that first, rather than use my previous idea.