Data Sheet

17
FORM NO.: FR2-015_ A Responsible Department：WBU Expiry Date: Forever
The information contained herein is the exclusive property of AzureWave and shall not be distributed, reproduced, or disclosed
in whole or in part without prior written permission of AzureWave.
3.4 Host Interface
3.4.1. SDIO Interface
The AW-CM276NF supports a SDIO device interface that conforms to the industry standard SDIO
Full-Speed card specification and allows a host controller using the SDIO bus protocol to access the
Wireless module device.
The AW-CM276NF acts as the device on the SDIO bus. The host unit can access registers of the
SDIO interface directly and can access shared memory in the device through the use of BARs and
a DMA engine.
The SDIO device interface main features include:
Supports SDIO 3.0 Standard
On-chip memory used for CIS
Supports SPI, 1-bit SDIO, and 4-bit SDIO transfer modes
Special interrupt register for information exchange
Allows card to interrupt host
3.4.1.1. SDIO Interface Signal Description
Pin Name
Signal
Name
Type
Description
SD_CLK
CLK
I/O
SDIO 1-bit mode: Clock
SDIO SPI mode: Clock
SD_CMD
CMD
I/O
SDIO 1-bit mode: Command line
SDIO SPI mode: Data input
SD_DAT[3]
DAT3
I/O
SDIO 4-bit mode: Data line bit [3]
SDIO 1-bit mode: Not used
SDIO SPI mode: Chip select (active low)
SD_DAT[2]
DAT2
I/O
SDIO 4-bit mode: Data line bit [2] or Read Wait (optional)
SDIO 1-bit mode: Read Wait (optional)
SDIO SPII mode: Reserved
SD_DAT[1]
DAT1
I/O
SDIO 4-bit mode: Data line bit [1]
SDIO 1-bit mode: Interrupt
SDIO SPI mode: Interrupt