Editing SD card (section)

====Version 1====
In version 1 of the SD specification, capacities up to 2&nbsp;GB{{efn|name="GiB"}} are calculated by combining fields of the CSD as follows:

 Capacity = ('''C_SIZE''' + 1) × 2<sup>('''C_SIZE_MULT''' + '''READ_BL_LEN''' + 2)</sup>
 where
  0 ≤ '''C_SIZE''' ≤ 4095,
  0 ≤ '''C_SIZE_MULT''' ≤ 7,
  '''READ_BL_LEN''' is 9 (for 512 bytes/sector) or 10 (for 1024 bytes/sector)

Later versions state (at Section 4.3.2) that a 2&nbsp;GB SDSC card shall set its READ_BL_LEN (and WRITE_BL_LEN) to indicate 1,024 bytes, so that the above computation correctly reports the card's capacity, but that, for consistency, the host device shall not request (by CMD16) block lengths over 512&nbsp;B.<ref name="SDHCspec"/>