Does XGPS 150 BT require jailbreak?

[tdott]

I'm trying to decide on which GPS add-on to buy.

I wanted to get confirmation on if the XGPS 150 BT reciever requires a jail-broken deceive? or if it will work with minimal setup / configuration.

I liked the Bad ELF GPS and don't mind that it is attached to the iPhone, but i don't like that it doesn't have NMEA support and they aren't providing Harry with the API to allow a higher refresh rate.

Does anyone have any suggestions?

[Harry]

Hi,

the XGPS150 does not require a jailbreak to be accessed directly. However, like the Bad Elf, it still does not pass through higher update rates. Finally, there is a new kid on the block named Emprum UltiMate GPS. It seems to support 5Hz without jailbreak. It is already on the Compatibility page but not rated from my side yet. I was told it works but I'm conservative until I have seen it I ordered one and will update the page as soon as I have tested.

So the status on the external GPS solution without jailbreak is as follows:

Code: Select all

            Direct NMEA access          High Update Rate
TomTom      YES                         NO, 1HZ CHIP
XGPS        YES                         NOT PASSED ON YET
Bad Elf     NOT YET                     NOT PASSED ON YET
UltiMate    NOT YET                     YES                     

Progress in this area is visible, but takes time. Currently, you need to place a bet (and put a lot of pressure on the manufacturers).

Harry

[tdott]

Thanks Harry, Will send each manufacture a note letting them know that if they provide you with the support you need I will consider buying their product.

[fast_eddie]

Any news on this Harry? Is the Ultimate the one to go for?

My 3GS was terrible at the track yesterday, it only managed to capture a single lap, and the data is pretty poor. I wasn't getting out of the red zone on the signal indicator.

Is this Iphone 4 GPS chip any better?

Ideally I want to go for an external unit, I notice the ultimate clips into the phone. The xgps would be better for me as i can tape it to my motorbike screen.

Cheers
Ed.

[Harry]

Hi,

I will post updates here. The Dual (XGPS) people still work on a solution. The UtliMate Emrum GPS has not yet arrived (take 2-3 weeks across the Atlantic and more important - customs).

- Harry

[csmarx]

I had an opportunity to try to the new Emprum UltiMATE GPS attachment for the iPhone this past weekend. I was at a 3 day event at Laguna Seca. As I reported to Harry - who is still wating for his - it seems to work! Here are my observations of using the Emprum chip vs. the TomTom Car Kit that I have been using:

The Good:
5 Hz update rate! It's fantastic in terms of detail. Instead of having 2 or 3 fixes to describe a corner, you now have 10-20 points. This makes it a semiserious data aquisition tool.
* It works right out of the box. Just plug it in a go.
* It's quite small and handy.
* It comes a with a USB charging cable that charges botht he internal GPS battery and the phone. Just get a USB car adapter for a few bucks.

The not so Good:
* The Emprum doesn't come with an integrated mount like the TomTom Car Kit, so you need a separate windscreen mount. This is less convenient. It's also a bit more bulky in that you now have the phone itself, then the GPS device sticking out of it, and then the charging plug sticking out of that, making it quite long.
* The connection between the Emprum device and the phone is so-so. If it's pulled a little one way or the other by the wire, the connection is lost. I had to tie up the charging wire to the mount so the wire wouldn't pull on the device.... Once I did that, the connection became much more reliable.
* With a 5 times higher data rate, Harry's lap timer fills up much more quickly due to the current limitation of 64k points in the database. I actually had to go and purge GPS data for my uninteresting laps several times to not run out of room. (Harry says that is being fixed in the next version - hopefully soon!)
* Lastly, with the higher data rate it now becomes evident that there is some "GPS noise" that makes it a bit jerky when looking at the speed plots, etc. This you wouldn't notice with the lower 1Hz data rate normally used. Harry may have to work on some smoothing of the higher frequency data...

All in all, I would say this. If you don't care about the data, but only the laptimes, then just stick with an integrated device like the TomTom Car Kit. It's convenient, reliable and easy to use. If you do care about the data, the Emprum is cheap and worth the little extra hassle.

-Christian

[tdott]

Thanks for your feedback, I took my iPhone4 and Harry's laptimer out this past weekend and I was a little disappointed at the speed accuracy, it was way off. It didn't come anywhere close to my top speed. I do plan to use an add-on GPS, but since the track season is almost done in Toronto, Canada. I will wait till next year, hopefully there is better support by then.

If you are interested, this is a video from my weekend.


http://youtu.be/Py1f4Q8hwD4

[Harry]

Hi,

There is an issue with the speed reported by the internal GPS sensor. It seems Apple kind of clips high speeds. This is the reason v14 has an expert setting for GPS Speed: set to 'Calculated' and LapTimer will runs its own speed calculation.

- Harry

[csmarx]

Harry,

Setting the expert setting to "Calculated" - is this a good idea even if you have an external GPS device like the TomTom Car Kit or the new Emprum UltiMATE?

Thanks,
-Christian

[Harry]

The XGPS150 is directly accessed using NMEA. With direct access the setting is ignored.
The Emprum needs to be tested. I'm not sure if the Emprum's data is manipulated like the internally generated GPS fixes are.
In general, I recommend using the calculated setting only when problems occur.

- Harry