Chapter 4 – SD Card Protocol Description
Revision 2.2
SanDisk SD Card Product Manual
© 2004 SanDisk Corporation
4-41
12/08/04
2)
R1b
is identical to R1 with the additional busy signal transmitted on the data line.
3)
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. The only bits transferred are [127...1]
of the CID and CSD; the reserved bit (0) in these registers is replaced by the end bit of the
response.
Table 4-20
Response R2
Bit Position
135 134
[133:128]
[127:1]
0
Width (bits)
1 1 6
127
1
Value
0 0
111111
x
1
Description
start bit
transmission bit
reserved
CID or CSD register incl.
internal CRC7
end bit
4)
R3
(OCR Register): response length 48 bits.
The contents of the OCR Register are sent as a response to CMD1.
Table 4-21
Response R3
Bit Position
47 46
[45:40]
[39:8]
[7:1]
0
Width (bits)
1 1 6 32 7
1
Value
0 0
111111
x
111111
1
Description
start bit
transmission bit
reserved OCR
Register reserved
end
bit
R4 and R5: responses are not supported.
5) R6 (Published RCA response): response length 48 bits. Bits 45:40 indicate the response
command’s index; in that case it will be 000011 (together w/bit 5 in the status bits it means
= CMD3. The 16 MSBs of the argument field are used for the published RCA number.
Table 4-22
Response R6
Bit Position
47 46
[45:40]
[39:8]
[7:1]
0
Width (bits)
1 1 6 32 7
1
Value
0 0
111111
x
111111
1
Description
start bit
transmission bit
reserved OCR
Register reserved
end
bit