PRELIMINARY
CYW43438
4.2 Generic SPI Mode
In addition to the full SDIO mode, the CYW43438 includes the option of using the simplified generic SPI (gSPI) interface/protocol.
Characteristics of the gSPI mode include:
■ Up to 50 MHz operation
■ Fixed delays for responses and data from the device
■ Alignment to host gSPI frames (16 or 32 bits)
■ Up to 2 KB frame size per transfer
■ Little-endian and big-endian configurations
■ A configurable active edge for shifting
■ Packet transfer through DMA for WLAN
gSPI mode is enabled using the strapping option pins. See Table 18 for details.
Figure 9. Signal Connections to SDIO Host (gSPI Mode)
SCLK
DI
DO
CYW43438
SD Host
IRQ
CS
Document Number: 002-14796 Rev. *K
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