Genesys Logic, Inc.
Downloaded by Sharon Huang Genesys Logic, Inc. on 04/28/2009
©Copyright 2001-2009 SD Group (Panasonic, SanDisk, Toshiba) and SD Card Association
Physical Layer Specification Version 3.00
Confidential iv
Table of Contents
1. General Description............................................................................................................1
2. System Features .................................................................................................................3
3. SD Memory Card System Concept....................................................................................5
3.1 Read-Write Property......................................................................................................................5
3.2 Supply Voltage...............................................................................................................................5
3.3 Card Capacity................................................................................................................................6
3.4 Speed Class ..................................................................................................................................7
3.5 Bus Topology .................................................................................................................................8
3.5.1 SD Bus ....................................................................................................................................8
3.5.2 SPI Bus ...................................................................................................................................9
3.6 Bus Protocol ................................................................................................................................10
3.6.1 SD Bus ..................................................................................................................................10
3.6.2 SPI Bus .................................................................................................................................13
3.7 SD Memory Card–Pins and Registers.........................................................................................14
3.8 ROM Card ...................................................................................................................................16
3.8.1 Register Setting Requirements .............................................................................................16
3.8.2 Unsupported Commands ......................................................................................................16
3.8.3 Optional Commands .............................................................................................................16
3.8.4 WP Switch.............................................................................................................................16
3.9 Ultra High Speed Phase I (UHS-I) Card ......................................................................................17
3.9.1 UHS-I Operation Modes........................................................................................................17
3.9.2 UHS-I Card Types .................................................................................................................17
3.9.3 Host and Card Combination..................................................................................................18
3.9.4 Bus Speed Modes Selection Sequence ................................................................................19
3.9.5 UHS System Block Diagram .................................................................................................20
3.9.5.1 Variable Sampling Host......................................................................................................... 20
3.9.5.2 Fixed Sampling Host............................................................................................................. 20
3.9.6 Summary of Bus Speed Mode ..............................................................................................21
4. SD Memory Card Functional Description .......................................................................22
4.1 General........................................................................................................................................22
4.2 Card Identification Mode..............................................................................................................23
4.2.1 Card Reset ............................................................................................................................23
4.2.2 Operating Condition Validation..............................................................................................23
4.2.3 Card Initialization and Identification Process ........................................................................25
4.2.3.1 Initialization Command (ACMD41)........................................................................................ 27
4.2.4 Bus Signal Voltage Switch Sequence ...................................................................................28
4.2.4.1 Initialization Sequence for UHS-I .......................................................................................... 28
4.2.4.2 Timing to Switch Signal Voltage............................................................................................ 29
4.2.4.3 Timing of Voltage Switch Error Detection.............................................................................. 30
4.2.4.4 Voltage Switch Command..................................................................................................... 30
4.2.4.5 Tuning Command ................................................................................................................. 31
4.2.4.6 An Example of UHS-I System Block Diagram....................................................................... 33
4.3 Data Transfer Mode.....................................................................................................................34
评论9