R3 (Ocr Register) - ST STM32F413 Reference Manual

RM0430
31.5.4

R3 (OCR register)

Code length: 48 bits. The contents of the OCR register are sent as a response to CMD1.
The level coding is as follows: restricted voltage windows = low, card busy = low.
Bit position
47
46
[45:40]
[39:8]
[7:1]
0
31.5.5 R4 (Fast I/O)
Code length: 48 bits. The argument field contains the RCA of the addressed card, the
register address to be read out or written to, and its content.
47
46
[45:40]
[39:8] Argument field
[7:1]
0
31.5.6 R4b
For SD I/O only: an SDIO card receiving the CMD5 will respond with a unique SDIO
response R4. The format is:
47
46
[45:40]
Width (bits
1
1
6
32
7
1
Bit position
[31:16]
[15:8]
[7:0]
Bit position
DocID029473 Rev 3
Secure digital input/output interface (SDIO)
Table 192. R3 response
Value
0
0
'111111'
X
'1111111'
1
Table 193. R4 response
Width (bits
1 0
1 0
6 '100111'
16 X
8 X
8 X
7 X
1 1
Table 194. R4b response
Width (bits
1 0
1 0
6 X
Description
Start bit
Transmission bit
Reserved
OCR register
Reserved
End bit
Value Description
Start bit
Transmission bit
CMD39
RCA
register address
read register contents
CRC7
End bit
Value Description
Start bit
Transmission bit
Reserved
1031/1284
1050