OCN4 Position Lag

tellwiley · 06-04-05, 09:52 PM

I recently switched GPS software from TomTom 2 to OnCourse Navagator 4. I wan't unhappy with TomTom, but my maps were pretty out of date. I won a copy of OCN4 from Aximsite (thanks again! :approve: ), so I loaded it up to see how it performed.

The interface is very different, but I've gotten used to it. It sort of supports landscape viewing (not very robust), which was something I've been looking for in a new GPS suite. All and all, not a bad app. But here's my beef...I'm experiencing major position lag (as compared to TomTom) when driving at ANY speed. At highway speeds, it's probably over 200 yds off of my actual position. When driving in unfamiliar areas, I could easily miss a highway exit in an urban area.

Can any one tell me if this is "normal" for OCN4? I suppose it could be a setting in the software, but I don't know what. TomTom was always very accurate with respect to position at all traveling speeds. I'm using a Holox 303MMF w/ BT slipper on my X30. Any thoughts, anyone?

JakeRich · 06-04-05, 11:02 PM

I never see positional lags of more than the inherent 1 second variety. If you are seeing lags of that magnitude something is wrong. How much RAM do you have before you run OCN? What else is running that might consume processor power?

gerbila · 06-05-05, 01:30 AM

Originally Posted by tellwiley

I recently switched GPS software from TomTom 2 to OnCourse Navagator 4.
Can any one tell me if this is "normal" for OCN4? I suppose it could be a setting in the software, but I don't know what. TomTom was always very accurate with respect to position at all traveling speeds. I'm using a Holox 303MMF w/ BT slipper on my X30. Any thoughts, anyone?

I found the same issue with OCN4. Of the GPS packages I'ved tried--Tomtom 2004, OCN4, and Mapopolis--it seems Tomtom has the best positional accuracy. Mapopolis comes a close second, and OCN4 is a distant third. The OCN4 lag is worst at highway speeds, and better at slower speeds. This, of course, makes sense somewhat, because the GPS unit updates position 1x/sec. However, Tomtom manages to maintain great accuracy, so apparently software should be able to compensate. I have stopped using OCN even though I think it has the best maps because of this issue.

On a side note, I used to use Mapopolis frequently until the A03 ROM update prevented me from running it in true VGA. So I dl'ed one of the betas, I forget which one, which is supposedly hi-res (but can not be run w/ any VGA hacks). I just came back from a trip to Vancouver, and the program was basically worthless for navigating around tight streets. The program lagged a good 5-10 sec after every turn. I am going to try the latest beta (.49 I think) and see if it works.

CalgaryCowboy · 06-05-05, 02:31 AM

With ocn4 lag was different from time to time. Have gotten into the habit of soft reseting before using and setting baud at 38000. Cold starting once in a while to clear out crap helps too.

tellwiley · 06-05-05, 12:02 PM

Thanks for the feedback.

Also, I'm running OCN4 from an SD card, whereas I used to run TomTom from internal memory (ah, those days when I had RAM to spare...). Could that be part of the problem?

dlweston · 06-05-05, 12:46 PM

I run OCN4 from a CF card and I do not normally see the lag you guys are discussing except if I use 3D mode. That is one of the things they are suppose to fix in OCN5. I also have about 28 MB of RAM free before I start OCN4. I have seen a lag twice. Once I had a couple programs running in the background. Closing them fixed me right up. The other time my memory was lower than normal for some reason, so I did a soft reset to clear the crap out. OCN4 likes memory. The more you give it to a point, the better it performs.

Koopah · 06-06-05, 08:51 PM

If I recall from an review I read about Tomtom 2004, it actually updates the screen more frequently that 1x/sec. This, of course, is done by the software extrapolating the estimated position (using mph/kph data?) rather than via a GPS signal each time. If I remember correctly, it actually estimates about 3x/sec.

Of note is that OCN v.5 will include sub-second positional updates as well.

FWIW,

Theo

RobMan · 06-07-05, 06:33 PM

Originally Posted by CalgaryCowboy

With ocn4 lag was different from time to time. Have gotten into the habit of soft reseting before using and setting baud at 38000. Cold starting once in a while to clear out crap helps too.

Hello CalgaryCowboy. How do you cold start? Through OCN or through the GPS info software that was included with the BT-338?

Thanks, Rob

CalgaryCowboy · 06-08-05, 01:07 AM

Originally Posted by RobMan

Hello CalgaryCowboy. How do you cold start? Through OCN or through the GPS info software that was included with the BT-338?

Thanks, Rob

It is the GPS info that came with the unit. Get this hint from the buygpsnow guys to get to work with my Destinator 3 demo. The documentation wasn't very good for that app.