bigger data card ?

GEOFFREY DEACON

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Im new to this game but Is there a larger data card for the sp III than the 128 meg one supplied or Is It best to get a second 128 card for euro trips without carrying a laptop, (not got one).
Also as anyone done the National Rally on a sp III alone?, I would love to try It..:confused:
 
GEOFFREY DEACON said:
Im new to this game but Is there a larger data card for the sp III than the 128 meg one supplied

No although it was rumoured that someone was cobbling up a 256Mb card.

Greg
 
GEOFFREY DEACON said:
Im new to this game but Is there a larger data card for the sp III
Why do you want a bigger card, the route calculation would be so slow as it would read all the data. Top Tip, only load the data you need, helps the unit calculate quicker. If you want more data for really long trips buy another card and put additional data on it.
john:)
 
Hi Roadrider:

I'm not sure I agree with your comment above in which you suggest that having more data (maps) on the data chip slows down the route calculation process.

The only 'slowdown' you will encounter when you have large amounts of data on the card (either a chip for a SP III or a CF card for a SP 26xx) is the INITIAL load of the card following the first time you turn the GPSR on after having loaded the maps on the chip. Subsequent power up cycles are not affected.

When the unit calculates a route (e.g. A to B), it only looks at the map segments needed to calculate the route, and it ignores segments that are not germane to the route being calculated. Proof of this is my own setup - a SP 2650 with a 1 gig chip and all of Europe (plus a bit of North America) loaded on the chip. If I ask the GPSR to calculate a route to the local gas station, it does not look at any of the data other than the single map segment that contains origin and destination.

What you might be thinking (perhaps what may have caused you to express the incorrect assumption) is that if you have a lot of map segments loaded, and then calculate a long route that spans just about all the segments you have loaded, then it will take a while to calculate the route. This is true enough, but the delay is caused by the route complexity, not the number of segments loaded.

PanEuropean
 
PanEuropean said:
Hi Roadrider:

I'm not sure I agree with your comment above in which you suggest that having more data (maps) on the data chip slows down the route calculation process.
Hi Pan European,
I stand corrected. :)
if you have lot's of data tiles loaded, will this affect the screen redraw speed???

What you might be thinking (perhaps what may have caused you to express the incorrect assumption) is that if you have a lot of map segments loaded, and then calculate a long route that spans just about all the segments you have loaded, then it will take a while to calculate the route. This is true enough, but the delay is caused by the route complexity, not the number of segments loaded.

So breaking long distance routes into smaller seperate routes is the answer then??

John
 
Hi John:

A very interesting question.

Until SP III software 2.45, whenever a route needed to be recalculated, the GPSR would recalculate the entire route, from present position to destination. If you had 300 miles ahead of you on your route, and the recalculation was prompted because you pulled off the road and went 50 feet up a farm lane to answer a call of nature, the GPSR would recalculate the whole darn route, all 300 miles of it. As you noted in your earlier post, this could take forever.

Beginning with 2.45, the route recalculation algorithm was changed, so that if the SP III got off route, it would only do a "quick" (partial) recalculation - meaning, what is the shortest path to take to get you back on the pre-existing route? In the case of the farm lane example, it would only have to recalculate a new route 50 feet back down the lane to your original route.

The GPSR now does 3 "quick" (partial) recalculations - recalculations that only consider how to get you from your present position to the closest logical re-interception point of your pre-existing route - and if you don't get re-established on your pre-existing route after the third "quick" recalculation, the GPSR gives up on you, and does a "complete" recalculation, from your present position all the way to your destination. You can invoke a full recalculation at any time by pressing the "recalculate" button. Recalculations invoked by pressing the 'recalculate route' button will always be full recalculations.

The SP 26xx has had this quick (partial) recalculation ability since day one of its public release. However, because of its much faster processor speed, recalculation speed is less of a problem, even if hundreds of miles are involved.

So, getting back to your question - it shouldn't be as much of a problem now to have a long route active, but you are correct, you will get much faster recalculations (when complete recalculations are done) if you have a series of short routes, rather than one long one.

I usually have a route active to a point no further than 2 hours riding in front of me, unless due to some rare circumstance (gotta catch a plane or similar) I positively MUST get to the destination in one long ride, and I want the ETA and miles remaining displays to give me info regarding my final destination.

PanEuropean

PS: About screen redraw - no, the amount of cartographic data loaded has no effect on screen refresh speed. Beyond a certain scale value (nominally about 5 miles, at default settings) the basemap is used to draw the screen, even though the data on the chip is still being used to calculate the route.
 


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