Datasheet

2. CID Register
The Card Identification (CID) register is 128 bits wide. It contains the card identification information used during the card
identification phase. Every individual flash card shall have a unique identification number. The structure of the CID register
is defined in the following paragraphs:
Name
Field
Width
CID-slice
Manufacturer ID
MID
8
[127:120]
OEM/Application ID
OID
16
[119:104]
Product name
PNM
40
[103:64]
Product revision
PRV
8
[63:56]
Product serial number
PSN
32
[55:24]
reserved
--
4
[23:20]
Manufacturing date
MDT
12
[19:8]
CRC7 checksum
CRC
7
[7:1]
not used, always 1
-
1
[0:0]
The CID Fields
MID
An 8-bit binary number that identifies the card manufacturer. The MID number is controlled, defined, and allocated to a SD
Memory Card manufacturer by the SD-3C, LLC. This procedure is established to ensure uniqueness of the CID register.
OID
A 2-character ASCII string that identifies the card OEM and/or the card contents (when used as a distribution media either
on ROM or FLASH cards). The OID number is controlled, defined, and allocated to a SD Memory Card manufacturer by
the SD-3C, LLC. This procedure is established to ensure uniqueness of the CID register.
Note: SD-3C, LLC licenses companies that wish to manufacture and/or sell SD Memory Cards, including but not limited to flash memory, ROM, OTP,
RAM, and SDIO Combo Cards.
SD-3C, LLC is a limited liability company established by Matsushita Electric Industrial Co. Ltd., SanDisk Corporation and Toshiba Corporation.
PNM
The product name is a string, 5 ASCII characters long.
PRV
The product revision is composed of two Binary Coded Decimal (BCD) digits, four bits each, representing an “n.m” revision
number. The “n” is the most significant nibble and “m” is the least significant nibble. As an example, the PRV binary value
field for product revision “6.2” will be: 0110 0010b