Seems we've had a few GT11s with write problems, so I thought I'd post Crashers problem, it's a bit weird and a virus or something may be involved, I'll try and remember the exact sequence, so you all can make you're own minds up.
He's had a history of problems getting his data out of the machine, that Elmo has helped sort out in the past, I've no idea of the details.
So yesterday before we sailed I checked his setup and it all looked normal, but later, when I tried to download from the card, there was the day's file on it but the file was empty.
Tried saving data logger to card, but that also produced an empty file.
Tried reading with navilink1 that also saved an empty file.
Put my card in his unit and tried saving data logger to it, that again produced an empty file, but also an 800kb file named cactus10.
(Well I assume that's were it came from, I'd formated my card last week and there was only last Friday's session on it prior to plugging into Crasher's unit.)
Can't find any info about any sort of malware with that kind of name.
A virus scan of this computer came up "clean"
To be on the safe side I wiped everything by reformatting cards and clearing datalogger
So today I did some testing by jogging round the park, (min speed set to 3kn)
Tried with navilink2 and that came up with an error, (sorry forget exactly what),
Tried it without memory card installed, still nothing in data logger.
Updated frimware to latest version, (V1.62(B1115), his old version was B0608T).
With no card in, data logger works, can read with navilink2 and will download to my memory card.
Seems to download to Crashers card but windows reports an unopenable corrupted card,
I reformatted the card and tried again with same result.
Then tried my card in there and jogged again, and it worked fine.
Not sure about this "cactus10" thing, don't know where it could have come from.
But the firmware in Crashers unit was bad and so is his memory card.
So can a crook memory card corrupt the firmware? Or vise versa?
Hopefully it'll be OK now.
Was Crasher still using that Sandisk 16 MB card I gave him?
I reformatted this card when I gave it to him, it was working well and giving good results.
It all sounds very strange... The only thing I can think of is that because the card size is so small, it's overwritten the flash enough times to wear it out in a couple of sectors. With larger cards the internal wear-balancing routine cleans this up so that it's normally not an issue.
This still wouldn't explain the cactus10 file, are you sure he wasn't abducted by aliens and his BGT-11 given a good probing?
Could it be a SD vs SDHC issue (different voltages)?
I am not so keen on this idea now as I think you implied that the GT-11 is able to reformat Crasher's card. This would suggest that the card is acceptable to the GT-11. I am assuming that the card reformat was done by the GT-11, not on a PC. On a PC it is possible to reformat cards/discs and inadvertently create different partitions that can confuse things.
Hope this doesn't muddy the issue!
Nebs, yes same 16MB card
Rindwinder, I reformatted it both ways, PC and BGT11, as Nebs says it's been working for several months, without a problem.
Snides, yours is the hardest question, frankly I wouldn't have a clue.
Very interesting, slowy may have a point about voltage needed.
I charged Crasher's unit up with the computer usb cable, it's taken ages!
But now guess what, I've managed to download the datalogger to it.
Strange thing is though I've got 2 cards come up one 14MB the other 1143GB they each have identical data. As it's only a 16MB card the last one is ludicrous. I saw the same thing with my card yesterday after I plugged it into Crasher's unit, but for both occasions I've been in Linux not Windows.
Although I've never seen this before, I have just done an update to the Linux installation.
Why do all these strange things happen together? it's so hard to tell what's causing what.
Anybody else noted problems related to lowish battery
EDIT,
Just booted into windows, no funny double card going on there just a perfectly good BSP file, so what's the go, was it all OK, just a low battery?
Surely there's a low battery warning or cutout?
We've had troubles in the past with a BGT-11 too.
Most problems relate to bad cards. If you have a bad card, or you get moisture into the card bay, the GPS will not be able to close the file it is writing to the card, resulting in a 0 size file on the card.
That is why I prefer to leave the data logger on all the time.
However, using windows Vista, I've had no luck whatsoever using Navilink to copy files off the device over USB. Navilink gets almost all the way through then crashes out and leave a 0 size file.
Luckily, the BGT-11 has a 'save to card' option to dump the logger memory to the card, and I've used that successfully more than once in the past to recover a "lost" data file after a device hang.
If your logger is also writing a 0 size file, that could be because the data logger is not configured correctly. For instance, you may have set it to not record any movement under 30 knots, in which case it may not record anything. Just a thought.
Perhaps the cactus was sent by an 'in propximity' bluetootrh device and Crasher, being the friendly guy that he is, was in charge of a receptive device ie BGT-11. It is well known that BT phone virus/crap is out there!
He could also have a dud GT-11 unit.
No warranty - this unit is no longer supported!
maybe
OK so is it possible to turn blue tooth off in the unit???
How do you tell if it's running?
I didn't see any mention of it when I ran thru the set-up
My understanding was that the bluetooth part of the unit simply transmitted lat and long out using bluetooth. This would enable you to have your NAVI on one arm, your mobile on the other, and track your progress in realtime on the web 
I didn't think that the bluetooth bit would accept files, or reflash firmware, or anything like that. It's just a copy of the serial NMEA data that normally gets spat out the USB port. Having bluetooth on will significantly affect battery life, however.
...But I could be wrong 
Decrep:
I accidentally let my unit run down once, it would turn on and then complain about a low battery before turning itself off. That day I left it in the car for an hour to charge, then it ran all day...
I think this might be a combination of low battery and old card. I would replace the card with a new 1 GB Sandisk one (seriously, has anyone seen the price of SD cards lately? It's daylight robbery... the customers are robbing the stores! I paid $16 for a 2 GB card the other day!) and see how you go.
Neb's the old 16MB card is definitely "iffy" crasher's unit works normally with my 1gb sandisk now, but not Crashers old card, it sometimes writes a valid "GPS data" file, but it doesn't write the normal sbn file to it, it will sometimes download the data logger sbp data to it OK.
Found the bluetooth toggle under settings, so I've turned that off, will tell Crasher he needs a new card.
