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TAAC—Defines the asynchronous part (relative to the miniSD Card clock (CLK)) of the read access time.

Table 3-11. TAAC Access Time Definition

TAAC Bit

Position

Code

2:0 time unit

0=1ns, 1=10ns, 2=100ns, 3=1µs, 4=10µs, 5=100µs, 6=1ms, 7=10ms

6:3 time value

0=reserved, 1=1.0, 2=1.2, 3=1.3, 4=1.5, 5=2.0, 6=2.5, 7=3.0, 8=3.5, 9=4.0,

A=4.5, B=5.0, C=5.5, D=6.0, E=7.0, F=8.0

7 Reserved

NSAC—Defines the worst case for the clock dependent factor of the data access time. The unit for NSAC is 100

clock cycles. Therefore, the maximal value for the clock dependent part of the read access time is 25.5k clock

cycles.

The total read access time N

as expressed in the Table 5-17 is the sum of TAAC and NSAC. It has to be computed

by the host for the actual clock rate. The read access time should be interpreted as a typical delay for the first data

bit of a data block from the end bit on the read commands.

TRAN_SPEED—Table 3-12 defines the maximum data transfer rate TRAN_SPEED.

Table 3-12. Maximum Data Transfer Rate Definition

TRAN_SPEED Bit Code

2:0 transfer rate unit

0=100kbit/s, 1=1Mbit/s, 2=10Mbit/s, 3=100Mbit/s, 4... 7=reserved

6:3 time value

0=reserved, 1=1.0, 2=1.2, 3=1.3, 4=1.5, 5=2.0, 6=2.5, 7=3.0,

8=3.5, 9=4.0, A=4.5, B=5.0, C=5.5, D=6.0, E=7.0, F=8.0

7 Reserved

CCC—The miniSD Card command set is divided into subsets (command classes). The card command class register

CCC defines which command classes are supported by this card. A value of ‘1’ in a CCC bit means that the

corresponding command class is supported. Table 3-13 lists the supported card command classes; refer to Table 4-3

for command class definitions.

Table 3-13. Supported Card Command Classes

CCC Bit Supported Card Command Class

0 class 0

1 class 1

......

11 class 11

1 2 ... 37 38 39 40 41 42 43 44 45 46 47 ... 113 114

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SanDisk SD032 Handbuch Seite 42