I suppose using a 5Hz GPS receiver brings a high amount of data processing.
Personally, I own a N95 8Gb, which is quite powerful in the Nokia smartphone range, but I really do not have any idea on the impact of RaceChrono on it. Is the N95 CPU powerful enough ? Does the bandwidth between the phone and GPS receiver wide enough ? Is there any bottleneck, if so, which one ?
Do you know if the hardware of some smartphones is a little bit short, if so, could you give us a matrix with recommendations about which kind of smartphone is good for a 5Hz GPS receiver, which one is known to be good only for 1Hz, etc.
My question comes from something I noticed when testing statically my new 818X. When running a fake session, I switched to Live Timer, and started to look at the "GPS time" counter. I figured out it wasn't regular, sometimes freezing... I do not know what the reason is, but I though it may be due to the difficulty to process data at the right speed.
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What kind of 5 Hz do you have? If you have set the GPS to 5 Hz via some software, it can run out of bandwidth. Try so that you enable only GGA and RMC sentences to 5 Hz and GSA and GSV would be only 1 Hz? Others are not needed.
Might also be some kind other Bluetooth problem.
RaceChrono uses a lot of CPU when drawing the maps etc (traveled route). Otherwise it draws power mainly due it tries to keep backlight on and the Bluetooth connections.
My GPS receiver is a Qstarz 818X, right out of the box. I didn't modify any value like GGA, RMC, GSA, ... but I'll have a look at them. I set the 5Hz mode with the switch on the side of the GPS case.
And I never let any program running at the same time.
My question was quite open : are the smartphone like N95 powerful enough to handle the data processing coming from a 5Hz GPS unit ? And do you know what is the first bottleneck ? CPU ? Bluetooth bandwidth ? any other ?
GPS Time is still freezing time to time, as previously mentionned (it freezes for at max 1 sec).
But, I had a closer look at the data in Traveled route and despite the fact that GPS time lags, Traveled route data are all there (every 0.2 sec I've got something).
Maybe the problem is only related to GPS time display ?
Note that I've also have the same behavior when setting the GPS to 1Hz (it freezes every 5-6 seconds).
One thing that comes to mind is that can you try to switch the "Storage selection" to your Phone memory (C:) just for testing? Maybe your memory card is slow for reason or another.
Also it might be you're running some background app that is freezing.
I have really no other program running (I switched off JBAK, Google Search, RotateMe, T9Nav, ... and all of these background tasks) and I still see the display freezing.
But if it doesn't affect the main purpose of RaceChrono (logging timestamped information about position), so it may be ignored, just a weird thing...
As in my initial post my main question was : "is my smartphone powerful enough for my new 5Hz GPS receiver ?" I think I've got the answer : "yes, it is, just don't rely on the GPS Time display, everything else works fine."
I just wonder if I'm the only one noticing this on a N95.
On my N95 I have no problems.
Gps time is not my priority if everything else works fine:)
Thank you for trying to find the reason.