User Manual

SPI Protocol Definition

5.2.3.5. Data Response

Every data block written to the device will be acknowledged by a data response token. It is one byte long and has

the following format:

76 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 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.

5.2.4. Data Tokens

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.

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 0

11111110

• 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

7 0

11111100

If Stop transmission is requested—Stop Tran

7 0

11111101