SD Command Response Registers

Versal Adaptive SoC Technical Reference Manual (AM011)

Document ID

AM011

Release Date

2023-10-05

Revision

1.6 English

The SD command response includes a 2-bit response type field and a 128-bit command response field.

The response types are listed in the following table.

Table 1. SD Command Response Types
Response Type	Index Check Enable	CRC Check Enable	Name of Response
00	0	0	No response
01	0	1	R2
10	0	0	R3 and R4
10	1	1	R1, R5, R6, and R7
11	1	1	R1b, R5b

The response bits are a concatenation of several registers. The response bit definitions are listed in the following table.

Table 2. SD Command Response Bit Definitions
Response Name	Description	Response Field	Registers
Response Name	Description	Response Field	32-bit Name	16-bit Name¹
R1 (normal) R1b (normal)	Card status	[39:8]	CMD_Resp0	Cmd_Response0 Cmd_Response1
R1b (Auto CMD12)	Card status		CMD_Resp3	Cmd_Response6 Cmd_Response7
R1 (Auto CMD23)	Card status		CMD_Resp3	Cmd_Response6 Cmd_Response7
R2	CID or CSD	[127:8]	CMD_Resp0 CMD_Resp1 CMD_Resp2 CMD_Resp3	Cmd_Response0 Cmd_Response1 Cmd_Response2 Cmd_Response3 Cmd_Response4 Cmd_Response5 Cmd_Response6 Cmd_Response7
R3	OCR for memory	[39:8]	CMD_Resp0	Cmd_Response0 Cmd_Response1
R4	OCR for I/O, etc.
R5, R5b	SDIO response
R6	Publish new RCA [31:16], etc.
The register reference manual defines eight 16-bit response registers. The standalone software defines four 32-bit registers.