Thread: Understanding OBD2

Dunno and don't care. My Aeroforce always tells me what I want to know, instantly. LOL

Instantly every 173 milliseconds.

Originally Posted by Bronco Boy

He means the data speed that the Chinese tool can read at. Data transfer speeds are different.....

USB 1.0 data rate, 12mb/s
USB 2.0 data rate, 480mb/s
Bluetooth data rate, 250mb/s

USB is much faster than bluetooth.

Thanks for the back up��

Here's how I quantify it,

No need to get all super technical about data speeds or what not were talking about things that cost about as much as a pack of cigarettes. I know that when I use my Bluetooth device to connect with torque pro on my tablet it connects just fine minus lag with real time data along with everything else. Its slow period. When I used my USB 2.0 OBDII cable and connect to the same software using the same device, its much faster plain and simple. It shouldn't need to be argued about I just want to use It since it clearly works better than the cheapo Bluetooth everyone on here seems to purchase.....

Either way the jobs gettin done no matter what just no sense spendin 100$ on a good Bluetooth device when I can buy a 15$ 2.0 cable with the same/ better results

It makes absolutely no difference. What is not understood that the PCM only sends information about 5 times a second, so that is the limit at which you can get information period. That's it, you can't get it any faster. I use DHP to log for tuning and it's a directly connected USB device and I also use BAFX which is Bluetooth connected to a tablet. It was with this "slow" device that I noticed that I was slipping the belt and was losing boost and only hitting about 6-7psi I then connected DHP and confirmed this. It doesn't matter what the data transfer rate is because it's not coming out fast enough to make any difference.

It's like saying your state of the art gaming computer is faster at playing Solitaire or minesweeper than a standard run of the mill office computer. Or saying your new 4K TV has a better picture than a standard 1080 HDTV when watching Hogans Hero's or Bonanza or watching the movie Miracle on 34th Street.

I mean if you see that much lag then you have other issues. The only time I have had issues was having too many other programs open on my tablet and it was slowing it down. My laptop that I use for tuning is a Thinkpad T530 with a 2.6 Ghz processor and 4Gb ram so it's no slouch and the only thing I use it for is tuning and for my Oscilloscope.

You really have no real data other other than your eyes and that's so subjective that it's invalid. Use a OBD2 Y and log with both systems and see what you have. That's a real test, everything else is just theoretical.


Edit: I use the tablet every day and have used this device for going on almost 2 years now.

Jeff

Obviously were not taking about the way the data is sent out seeing as how everyone here is basicly driving the same cars with the same pcms so its all the same. I'm talking about how the software recieves the data which can be controlled by what device you are using. USB 2.0 does that faster than Bluetooth and WiFi. I'm not sure how this became a pcm data speed rate debate when were talking about obdII protocol devices and how the mini elm is a piece of **** to communicate with. Dont need data charts or to google speed rates to point that out....

Basically everything you are arguing is pointless since the rate in which data arrives plays a bigger part in when it's displayed than the latency of the devices receiving the data. I'm not sure where you got your degree from but they didn't teach you much.

Jeff

Yea but were not talking about speed rate at which the data arives when this thread was about a mini elm 327 Bluetooth device and how its crap. You wanna throw out numbers you go right ahead, I thought this site was about sharing what everyone uses to help others but I guess every once in a while someone's just gotta throw stones for no reason...

I guess I just don't understand. The data rate is slow, but it's still faster than you can even blink so why is it even an issue? I just don't understand why you are making a fuss about something that is arbitrary. You say I can throw out numbers all I want is like saying "you can share all the facts you have but I'm still saying this is better than that in a practical sense with no evidence."

I mean people are slow as hell we are slow to take in information we are slow to process and react to information. Peoples reaction times are so slow its ridiculous to think that Bluetooth over USB is going to help anything. I mean our eyes react slow, like reallly really slow. You do realize that anything over about 20Hz looks like it's a solid light? Try it sometime.

This would be a totally different conversation if it was relevant to what we do with these devices. I'll agree that you are right on the transfer speeds between Bluetooth and USB, but does it make a difference in the price of tea in China? Does it help us in anyway? Does it matter at all that the transfer rate is the speed of light or the speed of sound? No it doesn't since it's still way faster than anything we can do anyway. Will it save a single piston from being chipped? I answer no it won't.

I'm all for sharing information that is for the good of the community but I wouldn't expect a Bucky Beaver Badge for posting information that's pretty much common knowledge, then arguing that it makes some kind of difference and we should all switch over to a USB devices because it's "faster".