Table 177. R4B Response; Table 178. R5 Response - ST STM32F405 Reference Manual

Secure digital input/output interface (SDIO)
[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]
[39:8] Argument field
[7:1]
0
Once an SD I/O card has received a CMD5, the I/O portion of that card is enabled to
respond normally to all further commands. This I/O enable of the function within the I/O card
will remain set until a reset, power cycle or CMD52 with write to I/O reset is received by the
card. Note that an SD memory-only card may respond to a CMD5. The proper response for
a memory-only card would be Present memory = 1 and Number of I/O functions = 0. A
memory-only card built to meet the SD Memory Card specification version 1.0 would detect
the CMD5 as an illegal command and not respond. The I/O aware host will send CMD5. If
the card responds with response R4, the host determines the card's configuration based on
the data contained within the R4 response.
31.5.7 R5 (interrupt request)
Only for MultiMediaCard. Code length: 48 bits. If the response is generated by the host, the
RCA field in the argument will be 0x0.
47
46
[45:40]
1056/1749
Table 176. R4 response (continued)
Bit position
Bit position
39
[38:36]
35
[34:32]
[31:8]
Bit position
Width (bits
7 X
1 1

Table 177. R4b response

Width (bits
1 0
1 0
6 x
16 X
3 X
1 X
3 X
24 X
7 X
1 1

Table 178. R5 response

Width (bits
1 0
1 0
6 '101000'
RM0090 Rev 18
Value Description
CRC7
End bit
Value Description
Start bit
Transmission bit
Reserved
Card is ready
Number of I/O functions
Present memory
Stuff bits
I/O ORC
Reserved
End bit
Value Description
Start bit
Transmission bit
CMD40
RM0090