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powercx
01-09-2007, 12:31 AM
I went to Fry's to grab the biggest memory card out there for Secure Digital. I found Pretech 8GB SD High Capacity Class 4 w/adapter. I was a little confuse why they labelled High Capacity. I looked at it, it's 8Gb, it's obviously High Capacity, duh. I came back, opened it, and it is incompatible with my ipaq hx2795b. And no firmware update for it either.

So I guess I'm returning it and maybe get something else.

Duncan
01-09-2007, 01:09 AM
SDHC (SD High Capacity) is a new variation on the SD format. Currently standard SD cards top out at 2GB in theory, and 4GB by means of a little trick (that not all devices can register). SDHC is able to come in 4GB and upwards - but it isn't backwards compatible (so most older devices can't use them).

Paul Martin
01-09-2007, 04:28 AM
SDHC (SD High Capacity) is a new variation on the SD format. Currently standard SD cards top out at 2GB in theory, and 4GB by means of a little trick (that not all devices can register). SDHC is able to come in 4GB and upwards - but it isn't backwards compatible (so most older devices can't use them).

Duncan,

I hadn't heard about the "trick". Do you have a link or list of compatible devices?

Duncan
01-09-2007, 05:10 AM
SDHC (SD High Capacity) is a new variation on the SD format. Currently standard SD cards top out at 2GB in theory, and 4GB by means of a little trick (that not all devices can register). SDHC is able to come in 4GB and upwards - but it isn't backwards compatible (so most older devices can't use them).

Duncan,

I hadn't heard about the "trick". Do you have a link or list of compatible devices?

Sorry - I was trying not to be too detailed... thus 'trick'. I know nothing more about this than was helpfully told to me by a company engineer (by way of explaining issues with standard 4GB cards).

The SD 1.1 standard (standard SD cards) officially maxes out at 2 GB and uses a FAT12/16 file system. SD cards can, by formatting with FAT32, theoretically go up to 4GB in size. This is apparentlt 'tweaking' the standard however and appears to be achieved in non-universal ways.

Lots of devices with SD slots don't recognise above 2GB. Those that do recognise standard 4GB cards seem to have problems with universal recognition even with regard to reliable name brands.

I assume the 4GB problem has something to do with how the SD 1.1 standard works with memory (Byte Addressing) as opposed to how the SD 2.0 (SDHC) standard works (Sector Addressing) - but we'd need to ask the SDA whey they set the official limt for SD 1.1 cards at 2GB when, on the surface, there should be not good reason for it not to be 4GB.

Nurhisham Hussein
01-09-2007, 07:38 AM
powercx, you can read more about the differences here (http://en.wikipedia.org/wiki/Secure_Digital_card#SD_and_SDHC_-_compatibility). As you can see it's not 'high capacity', it's 'High Capacity'. :wink:

PPCRules
01-09-2007, 06:34 PM
But, we should, concievably, be able to get such a thing as a CF adapter that will take 4+GB SDHC cards. Then if we obtain other devices (cameras, digital audio players, etc) that accommodates SDHC, we can have interchangability with our current PocketPCs (interchangability being very valuable in my experience + opinion).

Yet another reason to never get a PocketPC w/o daul (SD+CF) slots.

powercx
01-10-2007, 07:42 AM
Thanks for the info, I'm just glad I got a dual format Pocket PC, CF and SD Card. But my CF is maxed out, unless if I can get a 16Gb Flash Memory. :)