Specifications

©Copyright 2001-2013 SD Group (Panasonic, SanDisk, Toshiba) and SD Card Association
Physical Layer Simplified Specification Version 4.10
161
7.3 SPI Mode Transaction Packets
7.3.1 Command Tokens
7.3.1.1 Command Format
All the SD Memory Card commands are 6 bytes long. The command transmission always starts with
the left most bit of the bit string corresponding to the command codeword. All commands are protected
by a CRC (see Chapter 4.5). The commands and arguments are listed in Table 7-3.
Bit position
47
46
[45:40]
[39:8]
[7:1]
0
Width (bits)
1
1
6
32
7
1
Value
'0'
'1'
x
x
x
'1'
Description
start bit
transmission bit
command index
argument
CRC7
end bit
Table 7-1: Command Format
7.3.1.2 Command Classes
As in SD mode, the SPI commands are divided into several classes (See Table 7-2). Each class sup-
ports a set of card functions. A SD Memory Card will support the same set of optional command classes
in both communication modes (there is only one command class table in the CSD register). The
available command classes, and the supported command for a specific class, however, are different in
the SD Memory Card and the SPI communication mode.
Note that except for the classes that are not supported in SPI mode (class 1, 3 and 9), the mandatory
required classes for the SD mode are the same for the SPI mode.
CMD58/59 in SD mode are different from those in SPI mode.
Card Command Class
(CCC)
0 1 2 3 4 5 6 7 8 9 10 11
Supported
commands
class
description
basic
reser
ved
block
read
reser
ved
block
write
erase
write
pro-
tec-
tion
lock
card
appli-
cat-
ion
spe-
cific
I/O
mode
switch
reser
ved
CMD0
Mandatory
+
CMD1
Mandatory
+
CMD5
Optional
+
CMD6
2
Mandatory
+
CMD8
3
Mandatory
+
CMD9
Mandatory
+
CMD10
Mandatory
+
CMD12
Mandatory
+
CMD13
Mandatory
+
CMD16
Mandatory
+
+
+
CMD17
Mandatory
+
CMD18
Mandatory
+
CMD24
Mandatory
1
+
CMD25
Mandatory
1
+