T
T
T
S
S
S
2
2
2
G
G
G
S
S
S
D
D
D
1
1
1
5
5
5
0
0
0
2GB 150x Secure Digital Card
Transcend Information Inc.
10
[14]
1
Copy flag
COPY
0 b
Not copied
[13]
1
Permanent write protection
PERM_WRITE_PROTECT
0 b
Not protected
[12]
1
Temporary write protection
TMP_WRITE_PROTECT
0 b
Not protected
[11:10]
2
File format
FILE_FORMAT
00 b
HD like FAT
[9:8]
2
ECC code
ECC
00 b
None
[7:1] 7
CRC
CRC
---
---
[0] 1 Not used always
｀
1
--- 1
b
---
(*1) Support command class 0,2,4,5,6,7,8. Include : Basic, Block read/write, Erase, Write protection, application
command, and Lock card. Not support 1,3. Include : Stream read/write.
(*2)~(*4) This field is not a constant value. The value will be changed by different flash memory.
6. Extended CSD Register (EXT_CSD)
The Extended CSD register defines the card properties and selected modes. It is 512 bytes long.
The most significant 320 bytes are the Properties segment, which defines the card capabilities and cannot be
modified by the host. The lower 192 bytes are the Modes segment, which defines the configuration the card is
working in. These modes can be changed by the host by means of the SWITCH command.
7. SD card Configuration Register (SCR)
The CSD register is another configuration register in SD card. SCR provides on SD card s special features that were
configured into the given card. The size of SCR is 64 bit.
For SD card only. SCR is a read only register.
