Secure Digital (SD) Card Protocol Description
SanDisk Secure Digital (SD) Card Product Manual, Rev. 1.9 © 2003 SANDISK CORPORATION
4-25
Current State
idle ready ident stby tran data rcv prg dis ina
CMD32
- - - - tran - - - - -
CMD33
- - - - tran - - - - -
CMD38
- - - - prg - - - - -
Class 7
CMD42
This is an SDA optional command supported by the SanDisk SD Card.
Class 8
CMD55 idle
-
-
stby
tran
data
rcv
prg
dis
-
CMD56;
RD/WR
=
0
- - - - rcv - - - - -
CMD56;
RD/WR
=
1
- - - -
data
- - - - -
ACMD6
- - - - tran - - - - -
ACMD13
- - - - tran - - - - -
ACMD22
- - - - tran - - - - -
ACMD23
- - - - tran - - - - -
ACMD18,25,26,38,
43,44,45,46,47,48,49
Refer to
SD Card Security Specification
for an explanation of the SD Security Features. The
SanDisk SD Card supports all the security related commands as explained in the specification.
ACMD41, card V
DD
range
compatible
ready
- - - - - - - - -
ACMD41,
card
is
busy
idle - - - - - - - - -
ACMD41, card V
DD
range not
compatible
ina - - - - - - - - -
ACMD42
- - - - tran - - - - -
ACMD51
- - - -
data
- - - - -
class 9- 11
CMD41; CMD43...CMD54,
CMD57-CMD59
Reserved
CMD60...CMD63
Reserved for manufacturer
4.10. Responses
All responses are sent via the CMD line. The response transmission always starts with the MSB. The response
length depends on the response type.
A response always starts with a start bit (always ‘0’), followed by the bit indicating the direction of transmission
(card = ‘0’). A value denoted by ‘x’ in the tables below indicates a variable entry. All responses except for the type
R3 (see below) are protected by a CRC. Every response is terminated by the end bit (always ‘1’).
There are four types of responses that are supported in the SanDisk SD Card. Their formats are defined as follows:
R1
(standard response): response length 48 bit.
