Specifications

©Copyright 2001-2013 SD Group (Panasonic, SanDisk, Toshiba) and SD Card Association
Physical Layer Simplified Specification Version 4.10
172
7.3.3 Control Tokens
Data block transfer is controlled by some tokens.
7.3.3.1 Data Response Token
Every data block written to the card will be acknowledged by a data response token. It is one byte long
and has the following format:
7
6
5
4
3
2
1
0
x
x
x
0
Status
1
The meaning of the status bits is defined as follows:
'010' - Data accepted.
'101' - Data rejected due to a CRC error.
'110' - Data Rejected due to a Write Error
In case of any error (CRC or Write Error) during Write Multiple Block operation, the host shall stop the
data transmission using CMD12. In case of a Write Error (response '110'), the host may send CMD13
(SEND_STATUS) in order to get the cause of the write problem. ACMD22 can be used to find the
number of well written write blocks.
7.3.3.2 Start Block Tokens and Stop Tran Token
Read and write commands have data transfers associated with them. Data is being transmitted or
received via data tokens. All data bytes are transmitted MSB first.
Data tokens are 4 to 515 bytes long and have the following format:
For Single Block Read, Single Block Write and Multiple Block Read:
• First byte: Start Block
7
6
5
4
3
2
1
0
1
1
1
1
1
1
1
0
• Bytes 2-513 (depends on the data block length): User data
• Last two bytes: 16 bit CRC.
For Multiple Block Write operation:
• First byte of each block:
If data is to be transferred then - Start Block Token
7
6
5
4
3
2
1
0
1
1
1
1
1
1
0
0
If Stop transmission is requested - Stop Tran Token
7
6
5
4
3
2
1
0
1
1
1
1
1
1
0
1
Note that this format is used only for Multiple Block Write. In case of a Multiple Block Read the stop
transmission is performed using STOP_TRAN Command (CMD12).