SanDisk SDMB-16-771 Product Manual - Page 34

MultiMediaCard Product Manual SECTOR_SIZE-The size of an erasable sector. The contents of this register is a 5 bit binary coded value, defining the number of write blocks (see WRITE_BL_LEN). The actual size is computed by increasing this number by one. A value of zero means 1 write block, 31 means 32 blocks. ERASE_GRP_SIZE-The size of an erasable group. The contents of this register is a 5 bit binary coded value, defining the number of sectors (see SECTOR_SIZE). The actual size is computed by increasing this number by one. A value of zero means 1 sector, 31 means 32 sectors. WP_GRP_SIZE-The size of a write protected group. The contents of this register is a 5 bit binary coded value, defining the number of Erase Groups (see ERASE_GRP_SIZE). The actual size is computed by increasing this number by one. A value of zero means 1 erase group, 31 means 32 erase groups. WP_GRP_ENABLE-A value of '0' means no group write protection possible. DEFAULT_ECC-Set by the card manufacturer. It defines the ECC code which is recommended for use. The field definition is the same as for the ECC field described later. R2W_FACTOR-Defines the typical block program time as a multiple of the read access time. The following table defines the field format. Table 4-17 R2W_FACTOR R2W_FACTOR 0 1 2 3 4 5 6,7 Multiples of Read Access Time 1 2 (write half as fast as read) 4 8 16 32 reserved WRITE_BL_LEN-Block length for write operations. See READ_BL_LEN for field coding. WRITE_BL_PARTIAL-Defines whether partial block sizes can be used in block write commands. WRITE_BL_PARTIAL='0' means that only the WRITE_BL_LEN block size can be used for block oriented data write. WRITE_BL_PARTIAL='1' means that smaller blocks can be used as well. The minimum block size is one byte. COPY-This bit 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" is application dependent and changes no card characteristics. PERM_WRITE_PROTECT-Permanently protects the whole card content against overwriting or erasing (all write and erase commands for this card are permanently disabled). The default value is '0', i.e. not permanently write protected. TMP_WRITE_PROTECT-Temporarily protects the whole card content from being overwritten or erased (all write and erase commands for this card are temporarily disabled). This bit can be set and reset. The default value is '0', i.e. not write protected. 34 SanDisk MultiMediaCard Product Manual Rev. 2 © 2000 SANDISK CORPORATION