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March 15, 2010 at 12:39 am #32105babakalParticipant
my laptop and my cam can not format the card,I checked and made sure it is not locked. I don’t know what to do!!!!!
March 24, 2010 at 12:53 am #176775Joe BallMemberGet a new camera and laptop!
Really, you should’ve read the fine print before you bought a 16 GB SDHC memory card. A LOT of devices will not read them.
From Wikipedia:
Devices that use SD cards identify the card by requesting a 128-bit identification string from the card. For standard-capacity SD cards, 12 of the bits are used to identify the number of memory clusters (ranging from 1 to 4096) and 3 of the bits are used to identify the number of blocks per cluster (which decode to 4, 8, 16, 32, 64, 128, 256 or 512 blocks per cluster).
In older 1.x implementations the standard capacity block was exactly 512 bytes. This gives 4096 x 512 x 512 = 1 gigabyte of storage memory. A later revision of the 1.x standard allowed a 4-bit field to indicate 1024 or 2048 bytes per block instead, yielding up to 4 gigabyte of memory storage. Devices designed before this change may incorrectly identify such cards, usually by misidentifying a card with lower capacity than is the case by assuming 512 bytes per block rather than 1024 or 2048.
For the new SDHC (2.0) implementation, 22 bits of the identification string are used to indicate the memory size in increments of 512 bytes. The SDCA currently allows only 16 of the 22 bits to be used, giving a maximum size of 32 GB. All SD cards with a capacity larger than 4 GB must use the 2.0 implementation at minimum. Two bits that were previously reserved and fixed at 0 are now used for identifying the type of card, 0=standard, 1=SDHC, 2=reserved, 3=reserved. Non-SDHC devices are not programmed to read this code and therefore cannot correctly identify SDHC or SDXC cards.
All SDHC readers work with standard SD cards.
Many older devices will not accept the 2 or 4 GB size even though it is in the revised standard. The following statement is from the SD Card Association specification:
“To make 2 GByte card, the Maximum Block Length (READ_BL_LEN=WRITE_BL_LEN) shall be set to 1024 bytes. However, the Block Length, set by CMD16, shall be up to 512 bytes to keep consistency with 512 bytes Maximum Block Length cards (Less than and equal 2 Gbyte cards).”
I would start by checking with your laptop and camera manufacturer and see if they at least CLAIM to support > 4GB SDHC cards.
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