
MultiMediaCard
TM
29
Sep.22.2005
Revision 0.3
VDD_R_CURR_MAX, VDD_W_CURR_MAX
The maximum values for read and write currents at the maximal power supply V
DD
are coded as follows:
The values in these fields are valid when the card is not in high speed mode. When the card is in high speed mode, the
current consumption is chosen by the host, from the power classes defined in the PWR_ff_vvv registers, in the EXT_CSD
register.
C_SIZE_MULT
This parameter is used for coding a factor MULT for computing the total device size (see ‘C_SIZE’). The factor MULT is
defined as 2
C_SIZE_MULT+2
.
ERASE_GRP_SIZE
The contents of this register is a 5 bit binary coded value, used to calculate the size of the erasable unit of the card. The
size of the erase unit (also referred to as erase group) is determined by the ERASE_GRP_SIZE and the
ERASE_GRP_MULT entries of the CSD, using the following equation:
size of erasable unit = (ERASE_GRP_SIZE + 1) * (ERASE_GRP_MULT + 1)
This size is given as minimum number of write blocks that can be erased in a single erase command.
ERASE_GRP_MULT
A 5 bit binary coded value used for calculating the size of the erasable unit of the card. See ERASE_GRP_SIZE section
for detailed description.
WP_GRP_SIZE
The size of a write protected group. The contents of this register is a 5 bit binary coded value, defining the number of erase
groups which can be write protected. The actual size is computed by increasing this number by one. A value of zero
means 1 erase group, 31 means 32 erase groups.
VDD_R_CURR_MAX
VDD_W_CURR_MAX
2:0
Code for current consumption @ V
DD
0=1mA; 1=5mA; 2=10mA; 3=25mA; 4=35mA; 5=45mA; 6=80mA; 7=200mA
C_SIZE_MULT
0
MULT
2
2
= 4
2
3
= 8
2
4
= 16
2
5
= 32
2
6
= 64
2
7
= 128
2
8
= 256
2
9
= 512
1
2
3
4
5
6
7