©Copyright
SDIO Simplified Specification Version 2.00
Table of Contents
1. General Description | 1 | |
1.1 | SDIO Features | 1 |
1.2 | Primary Reference Document | 1 |
1.3 | Standard SDIO Functions | 1 |
2. SDIO Signaling Definition | 2 | |
2.1 | SDIO Card Types | 2 |
2.2 | SDIO Card modes | 2 |
2.2.1 SPI (Card mandatory support) | 2 | |
2.2.2 | 2 | |
2.2.3 | 2 | |
2.3 | SDIO Host Modes | 2 |
2.4 | Signal Pins | 3 |
3. SDIO Card Initialization | 4 | |
3.1 | Differences in I/O card Initialization | 4 |
3.2 | The IO_SEND_OP_COND Command (CMD5) | 10 |
3.3 | The IO_SEND_OP_COND Response (R4) | 11 |
3.4 | Special Initialization considerations for Combo Cards | 12 |
3.4.1 | 12 | |
3.4.2 Using a Combo Card as SDIO only or SD Memory only after Combo Initialization | 12 | |
3.4.3 Acceptable Commands after Initialization | 12 | |
3.4.4 Recommendations for RCA after Reset | 12 | |
3.4.5 Enabling CRC in SPI Combo Card | 14 |
4. Differences with SD Memory Specification | 15 | ||
4.1 | SDIO Command List | 15 | |
4.2 | Unsupported SD Memory Commands | 15 | |
4.3 | Modified R6 Response | 16 | |
4.4 | Reset for SDIO | 16 | |
4.5 | Bus Width | 16 | |
4.6 | Card Detect Resistor | 17 | |
4.7 | Timings | 17 | |
4.8 | Data Transfer Block Sizes | 18 | |
4.9 | Data Transfer Abort | 18 | |
4.9.1 | Read Abort | 18 | |
4.9.2 | Write Abort | 18 | |
4.10 | Changes to SD Memory Fixed Registers | 18 | |
4.10.1 | OCR Register | 19 | |
4.10.2 | CID Register | 19 | |
4.10.3 | CSD Register | 19 | |
4.10.4 | RCA Register | 19 | |
4.10.5 | DSR Register | 19 | |
4.10.6 | SCR Register | 19 | |
4.10.7 | SD Status | 19 | |
4.10.8 | Card Status Register | 19 |
5. New I/O Read/Write Commands | 21 | |
5.1 | IO_RW_DIRECT Command (CMD52) | 21 |
5.2 | IO_RW_DIRECT Response (R5) | 22 |
5.2.1 CMD52 Response (SD modes) | 22 | |
5.2.2 R5, IO_RW_DIRECT Response (SPI mode) | 23 | |
5.3 | IO_RW_EXTENDED Command (CMD53) | 24 |
5.3.1 CMD53 Data Transfer Format | 25 |
iv