SDHC CSD Decoder

Secure Digital (High Capacity - CSD Version 2.0) Card CSD Decoder

by Gough Lui

Enter the CSD as a hex string (as reported by cat /sys/block/device/mmcblk1/csd):

Decoded Result

CSD Structure: describes version of CSD structure

Data Read Access Time 1: defines Asynchronous part of the read access time

Data Read Access Time 2: worst case clock dependent factor for data access time

Max Data Transfer Rate: sometimes stated as Mhz

Card Command Classes:

Max Read Data Block Length:

Partial Blocks for Read Allowed:

Write Block Misalignment:

Read Block Misalignment:

DSR Implemented: indicates configurable driver stage integrated on card

Device Size: to calculate the card capacity excl. security area ((device size + 1)* 512kbytes

Erase Single Block Enabled:

Erase Sector Size: size of erasable sector in write blocks

Write Protect Group Size:

Write Protect Group Enable:

Write Speed Factor: block program time as multiple of read access time

Max Write Data Block Length:

Partial Blocks for Write Allowed:

File Format Group:

Copy Flag:

Permanent Write Protection:

Temporary Write Protection:

File Format:

CRC7 Checksum + always 1 in LSB: