MultiMediaCard Product Manual
SanDisk MultiMediaCard Product Manual Rev. 2 © 2000 SANDISK CORPORATION
55
R1
(standard response): response length 48 bit.
Bits 45:40 indicate the index of the command which is responded to.The status of the card is coded in 32
bits.
Bit Position
47
46
[45:40]
[39:8]
[7:1]
0
Width (bits)
1
1
6
32
7
1
V a l u e
‘0’
‘0’
x
x
x
‘1’
Description
start bit
transmission bit
command index
card status
CRC7
end bit
R1b
is identical to R1 with the additional busy signaling via the data.
R2
(CID, CSD register): response length 136 bits.
The content of the CID register is sent as a response to CMD2 and CMD10. The content of the CSD
register is sent as a response to CMD9. Only
bits [127...1] of the CID and CSD are transferred, bit [0] of
these registers is replaced by the end bit of the response.
Bit Position
135
134
[133:128]
[127:1]
0
Width (bits)
1
1
6
127
1
V a l u e
‘0’
‘0’
‘111111’
x
‘1’
Description
start bit
transmission bit
reserved
CID or CSD register incl.
internal CRC7
end bit
R3
(OCR register): response length 48 bits.
The contents of the OCR register is sent as a response to CMD1.
Bit Position
47
46
[45:40]
[39:8]
[7:1]
0
Width (bits)
1
1
6
32
7
1
V a l u e
‘0’
‘0’
‘111111’
x
‘1111111’
‘1’
Description
start bit
transmission bit
reserved
OCR register
reserved
end bit
Responses R4 and R5 are not supported.