spi_s_async_set_char_size

Set SPI transfer character size in number of bits.

int32_t spi_s_async_set_char_size(
    struct spi_s_async_descriptor * spi,
    const enum spi_char_size char_size
)

The character size (spi_char_size_t) influence the way the data is sent/received. For char size <= 8-bit, data is stored byte by byte. For char size between 9-bit ~ 16-bit, data is stored in 2-byte length. Note that the default and recommended char size is 8-bit since it's supported by all system. Note that the SPI must be disabled to change character size. Also it affects buffer accessing, the ring buffer should be flushed before changing it to avoid conflicts.

Parameters

spi

Type: struct spi_s_async_descriptor Struct *

Pointer to the HAL SPI instance.

char_size

Type: const enum spi_char_size

The char size (~32, recommended 8).

Returns

Type: int32_t

Operation status.

ERR_NONE

Success.

ERR_DENIED

Not Ready

ERR_BUSY

Busy, CS activated.