Datasheet

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datasheet SD Card
Rev. 1.0
MMBTFxxGWBCA-xMExx
4.3.3 CSD Register (CSD Version 1.0)
The Card-Specific Data register provides information on how to access the card contents. The CSD defines the data format, error correction type, maxi-
mum data access time, data transfer speed, whether the DSR register can be used etc. The programmable part of the register (entries marked by W or E,
see below) can be changed by CMD27. The type of the entries in the table below is coded as follows: R = readable, W(1) = writable once, W=multiple
writable.
[Table 4-6] : The CSD Register Fields (CSD Version 1.0)
Name Field Width
Cell
Type
CSD-slice
CSD Value
4GB 8GB 16GB
CSD structure CSD_STRUCTURE 2 R [127:126] Version 1.0
Reserved - 6 R [125:120] -
Data read access-time 1 TAAC 8 R [119:112] N/A
Data read access-time 2
in CLK cycles (NSAC*100)
NSAC 8 R [111:104] N/A
Max. Data transfer rate TRAN_SPEED 8 R [103:96] N/A
Card command classes CCC 12 R [95:84] N/A
Max. read data block length READ_BL_LEN 4 R [83:80] N/A
Partial blocks for read allowed READ_BL_PARTIAL 1 R [79:79] N/A
Write block misalignment WRITE_BLK_MISALIGN 1 R [78:78] N/A
Read block misalignment READ_BLK_MISALIGN 1 R [77:77] N/A
DSR implemented DSR_IMP 1 R [76:76] N/A
Reserved - 2 R [75:74] -
Device size C_SIZE 12 R [73:62] N/A
Max. read current @ V
DD
min
VDD_R_CURR_MIN 3 R [61:59] N/A
Max. read current @ V
DD
max
VDD_R_CURR_MAX 3 R [58:56] N/A
Max. write current @ V
DD
min
VDD_W_CURR_MIN 3 R [55:53] N/A
Max. write current @ V
DD
max
VDD_W_CURR_MAX 3 R [52:50] N/A
Device size multiplier C_SIZE_MULT 3 R [49:47] N/A
Erase single block enable ERASE_BLK_EN 1 R [46:46] N/A
Erase sector size SECTOR_SIZE 7 R [45:39] N/A
Write protect group size WP_GRP_SIZE 7 R [38:32] N/A
Write protect group enable WP_GRP_ENABLE 1 R [31:31] N/A
Reserved (Do Not Use) 2 R [30:29] -
Write speed factor R2W_FACTOR 3 R [28:26] N/A
Max. write data block length WRITE_BL_LEN 4 R [25:22] N/A
Partial blocks for write allowed WRITE_BL_PARTIAL 1 R [21:21] N/A
Reserved - 5 R [20:16] -
File format group FILE_FORMAT_GRP 1 R/W(1) [15:15] N/A
Copy flag (OTP) COPY 1 R/W(1) [14:14] N/A
Permanent write protection PERM_WRITE_PROTECT 1 R/W(1) [13:13] N/A
Temporary write protection TMP_WRITE_PROTECT 1 R/W [12:12] N/A
File format FILE_FORMAT 2 R/W(1) [11:10] N/A
Reserved 2 R/W [9:8] -
CRC CRC 7 R/W [7:1] N/A
Not used, always ’1’ - 1 - [0:0] -