SD card size?

Discussion related to the Garmin GPSMAP 66i GPSr
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sky-eye
Posts: 19
Joined: Thu Jan 20, 2022 4:17 pm

SD card size?

Unread post by sky-eye »

The specs of the 66i say the SD card can be 32G
OK yes, under normal windows, one can not format bigger cards the 32G to fat32.

But, there are many ways to format cards, so one can surely format bigger cards as 64 or 128 to fat32.

I tested this, it seems to work. However I do not know what unexpected problems could came up in future. Are there any experience on this?


Reason:
Maps are getting bigger and bigger, I need lot of maps to carry locally and plain 32G does not hold all the items any more.

Any advise?
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GPSrChive
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Joined: Fri Jan 20, 2017 11:29 pm

Re: SD card size?

Unread post by GPSrChive »

You can format any size micro SD card you like to FAT32, but the GPSMAP 66i is only going to recognize 32GB. Which 32GB you ask? Nobody knows....
sky-eye
Posts: 19
Joined: Thu Jan 20, 2022 4:17 pm

Re: SD card size?

Unread post by sky-eye »

Not which card

It is simply so, any card formated to fat32 is accepted, I have tested different once with 32, 64 128 and the size was never a problem. The same data which lead to problems did have same problems on a 16 or 32 card.

My Q is just if there are any mechanisms which may cause harm and either cause crashes or destroy the data on the card because of the size of the card itself.
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GPSrChive
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Re: SD card size?

Unread post by GPSrChive »

I'll try again :D

A Garmin device limited to 32GB of external storage will only use 32GB of the available space on the installed microSD card, regardless of how much storage space is physically available.

If you load more than 32GB of data to a card larger than 32GB, you have no way of knowing which data the Garmin device will read and use, and which data the Garmin device will simply ignore.
paulxtr
Posts: 32
Joined: Wed Feb 27, 2019 11:13 pm

Re: SD card size?

Unread post by paulxtr »

I have 31.7 GB of maps (img format) and 19 GB of BirdsEye (jnx format) as well as numerous tracks, routes, poi's etc. installed on a 128 GB microsd in both my GPSMAP 66s and GPSMAP 62sc.

I can't claim to have looked at every tile of every map, but I've never noticed any missing data.

On the other hand, my Oregon 450 is limited to a maximum microsd card size of 32 GB and it doesn't boot when a larger one is fitted.
sky-eye
Posts: 19
Joined: Thu Jan 20, 2022 4:17 pm

Re: SD card size?

Unread post by sky-eye »

well the amount of what is read in is anyway limited by the number of segments.
Most of my files will be renamed from .img to .xxx so they will not be read

So far it seems to work, 128 card is read without problems

The Q is just if there should be some king of overflow or something like that be expected
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