SanDisk SD Card

Revision 2.2Chapter 3 – SD Card Interface DescriptionSD Card Product ManualTable 3-26Data Block LengthWRITE_BL_LEN0 to 8 ReservedBlock Length9 2 9 = 512 bytes11 2 11 = 2048 bytes12-15 Reserved……• WRITE_BL_PARTIAL—defines whether partial block sizes can be used in blockwrite commands.Table 3-27 Partial Data Block SizeWRITE_BL_PARTIALDefinition0 Only the WRITE_BL_LEN block size, and its partial derivatives inresolution of units of 512 blocks, can be used for block oriented datawrite.1 Smaller blocks can be used as well. The minimum block size is onebyte.• FILE_FORMAT_GROUP—indicates the selected group of file formats. This field isread-only for ROM.• COPY—marks the card as an original (0) or non-original (1). Once set to non-original,this bit cannot be reset to original. The definition of “original” and “non-original” isapplication dependent and does not change card characteristics.• PERM_WRITE_PROTECT—permanently protects the entire card contents againstoverwriting or erasing (all write and erase commands for this card are permanentlydisabled). The default value is 0 (i.e., not permanently write protected).• TMP_WRITE_PROTECT—temporarily protects the whole card content from beingoverwritten or erased (all write and erase commands for this card are temporarilydisabled). This bit can be set and reset. The default value is 0 (i.e., not write protected).• CONTENT_PROT_APP—indicates whether the content protection application issupported. MultiMediaCards that implement the content protection application willhave this bit set to “1.”• FILE_FORMAT—indicates the card’s file format. This field is read-only for ROM.The formats are defined in Table 3-28.Table 3-28 File FormatFILE_FORMAT_GRP FILE_FORMAT Type0 0 Hard disk-like file system with partition table.0 1 DOS FAT (floppy-like) w/boot sector only (no partitiontable).0 2 Universal file format.0 3 Others/unknown.1 0, 1, 2, 3 Reserved.• CRC—carries the checksum for the CSD content. The host must recalculate thechecksum for any CSD modification. The default corresponds to the initial CSDcontents.© 2004 SanDisk Corporation 3-19 12/08/04