From HwB
SDIO=Secure Digital Input/Output
Version of Secure Digital used to connect peripherals.
Three different modes are supported:
- SD 4-bit mode (mandatory on high-speed cards)
- SD 1-bit mode (mandatory on all cards)
- SPI mode (mandatory on all cards)
[edit] Pinout
[edit] SD 4-bit mode
| Pin | Name | Description
|
| 1 | CD/DAT[3] | Data line 3
|
| 2 | CMD | Command line
|
| 3 | VSS1 | Ground
|
| 4 | VDD | Supply voltage
|
| 5 | CLK | Clock
|
| 6 | VSS2 | Ground
|
| 7 | DAT[0] | Data line 0
|
| 8 | DAT[1] | Data line 1
|
| 9 | DAT[2] | Data line 2
|
[edit] SD 1-bit mode
| Pin | Name | Description
|
| 1 | n/c | Not used
|
| 2 | CMD | Command line
|
| 3 | VSS1 | Ground
|
| 4 | VDD | Supply voltage
|
| 5 | CLK | Clock
|
| 6 | VSS2 | Ground
|
| 7 | DATA | Data line
|
| 8 | IRQ | Interrupt
|
| 9 | RW | Read/Write (optional)
|
[edit] SPI mode
| Pin | Name | Description
|
| 1 | CS | Card Select
|
| 2 | DI | Data input
|
| 3 | VSS1 | Ground
|
| 4 | VDD | Supply voltage
|
| 5 | CLK | Clock
|
| 6 | VSS2 | Ground
|
| 7 | DO | Data output
|
| 8 | IRQ | Interrupt
|
| 9 | n/c | Not used
|