Thread: nüvi 3x0 SD & Map Size Limits

This discussion is as much to do with the smaller .IMG file size limit of 2,147,483,647 Bytes [2GiB minus 1 Byte] required by some older Garmin units and GMXT, and then it's moot if you can simply put the <2GiB image on a 4GB card as is pointed out in the above posts for only those units capable of reading FAT32. The confusion over the decimal Gigibyte [GB] and the binary Gibibyte [GiB] is never-ending and can unfortunately be further perpetuated by use of non-standard abbreviations such as 'gig' [not a criticism, i do it too at times but avoid it in sensitive situations such as these discussion].

When Windows reports in 'GB' as in the pics above, it's actually sticking with the original binary convention of 2 to the power of 30 i.e. 1,073,741,824 bytes for a Gigabyte, which is historically correct but is now not the interpretation thrust upon us some time back by the sneaky drive manufacturers who decided to measure storage space in decimal i.e. 1,000,000,000 for a Gigabyte which is 10 to the power of 9. Of course, that all started back in the '90s when were were measuring flash drives and SD cards only in Megabytes [1MB is 1,048,576 bytes in binary base of 2^20 and of course it's 1,000,000 bytes in decimal base of 10^6 so the difference is relatively small, >5%], but now when we measure hard drives in Terabytes and 1TiB is 1,099,511,627,776 and in decimal TB it's only 1,000,000,000,000 bytes we're looking at ~10%. Soon we'll be measuring our home PC HDD in Petabytes [or Pebibytes if you like] and the difference between binary and decimal is then profound. Don't even try to think about Exabytes.

How did this get handled by the the International Electrotechnical Commission (IEC)? Over 15 years ago in December 1998 they decided to 'standardize' the terminology by making KB/MB/GB/TB etc decimal and KiB/MiB/GiB/TiB etc binary. Unfortunately Microsoft didn't see it that way so confusion has reigned ever since because to M$ when you talk computers everything is binary.....

Let's just try to use the 'correct' abbreviations: GB for Gigabyte, GiB for Gibibyte and not use GB when we mean GiB like M$ does, and resist any usage such as 'gig' please.

Above posts moved from [Only registered and activated users can see links. ].

Here are some facts about 3x0. No hearsay or from another forum or even from Garmin, but from my experience with a couple of 3 series. The unit can see at least a 8GB Sandisk SDHC formatted in FAT32 [8 'GB' = 7,939,817,472 bytes = 7.39 GiB]. It can use Full NA 2014.20 which is 1.88 GiB binary (2,025,357,312 bytes, or ~2.025 GB decimal) but it cannot recognise AU Topo V4 which is 2.84 GiB (3,050,766,336 bytes).



This is definitive as far as i'm concerned: 300 series is not limited to 2GB card, but is limited to under 2GiB map image file.

@quebec001
NA 2014.40 is over 2GiB. Can you please post a screenshot of the Map Info page showing the complete NA 2014.40 recognised by your 350?

I've now tried 5 different 3x0 series nuvis, 1 x AU 300, 2 x AU 310 and 2 x NA 360 none of which will recognise a map image over 2GiB but will display 2014.30 which is indeed 2,122,612,736 bytes or ~1.98GiB, just under 2GiB.

All 5 units will also accept a Toshiba 16GB microSDHC Class 6 and a Sandisk 64GB microSDXC-I [reformatted to FAT32] in an SD Adapter. Definitely card size is not an issue in nuvi 3x0 series just as it isn't in later nuvi series.

**** !! **** and reshit!!!!
I remade my duty

• I tryed Garmin City Navigator Europe 2013.40 at 2.83gig ( so i am not at 100% if its just NT and not NTU) My nuvi 360begins scanning but cant finish scan new map and inside info map cant saw
• I reinstalled garmin topo canada v4, i made on "SD of 2.84gig and same Europe my nuvi 360 begins scanning but cant finish scan new map and inside info map cant saw new map!

So think is not normal and no new firmware !

Sorry M. Smokefree and M. tli, I have to make my mea culpa

Originally Posted by tli

No problem, I'm still curious whether splitting the full mapset into two img files, each smaller than 2GiB, would work. Please test if you have a chance--unless Neil has tried already... thanks!

i will trye, so just for one test, because , old map inside give nice backup if i lose my external SD or broke this SD


so if you put put de same name map inside and SD, gps dont like start ?

so i made one test, i using City navigator North america NT 2014.40 without Mexico in my SD card, and ill made City navigator North Americ Nt 20140 Mexico only inside my gps gmapprom.img
ill give my feed back after

Originally Posted by quebec001

so if you put put de same name map inside and SD, gps dont like start ?

so i made one test, i using City navigator North america NT 2014.40 without Mexico in my SD card, and ill made City navigator North Americ Nt 20140 Mexico only inside my gps gmapprom.img
ill give my feed back after

You do not have any problem using this way. File name is not matter but only gmapsupp.img on SD is available and maybe is not available gmapprom1.img inside. We use this method many year... Good luck!

Originally Posted by Giomen

...... maybe is not available gmapprom1.img inside. ........

As usual you make me justify my uncertain memory G .... [sighhh ...]

Here is a US 360 with NA 2014.20 ALL [1.88GiB] gmapsupp on the SD card; Internally it has Raratonga gmapoem [not de-selectable], AUNZ gmapsupp, Norfolk Island gmapprom, Bangladesh (BGD) gmapprom1:




gmapsup2 won't work internally, and of course gmapsupp is the only name usable in SD. gmapsup1 does not work in SD unlike as enabled by later US/EU fw for 2, 4 and 7 series.

Originally Posted by quebec001

........
so if you put put de same name map inside and SD, gps dont like start ? ........

Absolutely not a problem even if identical parts of the same map is present both internally and externally proved the version is identical. This is, you could have 2014.40 US & CA internally and 2014.40 US & MX externally and there wouldn't be a conflict because the duplicated tiles are identical. Mixing versions with no duplicated tiles will be ok [e.g. 2014.40 US and 2014.30 CA & MX], doing that with overlapping areas can bring you grief very probably though in actual use, but won't prevent your unit from starting. I had a problem years ago 'in the wild' with the OEM US lower 48 map teamed with a later version of CA 'cos i forgot that the CA map also included the US border States. Made 'Shuffle off to Buffalo' quite a trail. Fortunately the CA was on the card so just took it out. On the other hand, i once bought a 1390 from a bloke who had travelled all the way from Perth to the Eastern seaboard of AU with an old version of Sensis AU onboard and a new Navteq AU on a microSD with both enabled. He said he hadn't had a problem. I didn't really believe that so used it for a few days the same. It ran erratically and the routes were strange but it didn't freeze or reboot. Took out the card and hard reset it and it ran perfectly.

...... i using City navigator North america NT 2014.40 without Mexico in my SD card, and ill made City navigator North Americ Nt 20140 Mexico only inside my gps gmapprom.img
ill give my feed back after

Perfectly acceptable. That will work for sure as Giomen said.