Response Formats; R1 (Normal Response Command); R1B; R2 (Cid, Csd Register) - ST STM32F205 series Reference Manual

Advanced arm-based 32-bit mcus

Hide thumbs Also See for STM32F205 series:

Table of Contents

Reserved for manufacturer.

Response formats

All responses are sent via the MCCMD command line SDIO_CMD. The response

transmission always starts with the left bit of the bit string corresponding to the response

code word. The code length depends on the response type.

A response always starts with a start bit (always 0), followed by the bit indicating the

direction of transmission (card = 0). A value denoted by x in the tables below indicates a

variable entry. All responses, except for the R3 response type, are protected by a CRC.

Every command code word is terminated by the end bit (always 1).

There are five types of responses. Their formats are defined as follows:

Code length = 48 bits. The 45:40 bits indicate the index of the command to be responded to,

this value being interpreted as a binary-coded number (between 0 and 63). The status of the

card is coded in 32 bits.

Bit position

It is identical to R1 with an optional busy signal transmitted on the data line. The card may

become busy after receiving these commands based on its state prior to the command

Code length = 136 bits. The contents of the CID register are sent as a response to the

CMD2 and CMD10 commands. The contents of the CSD register are sent as a response to

Table 125. Application-specific commands (continued)

Secure digital input/output interface (SDIO)

Abbreviation

RM0033 Rev 8

Transmission bit

Command index

Do you have a question about the STM32F205 series and is the answer not in the manual?