spi.c

Source file: spi.c

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Function: spi_init

int spi_init(unsigned int speed_hz)

Initialize the SPI bus.

Parameters:

Name Type Description
speed_hz unsigned int Clock speed in Hz.

Returns: 0 on success.

Function: spi_transfer

int spi_transfer(const void *tx, void *rx, int len)
Example
uint8_t tx[] = {0x01, 0x02};
uint8_t rx[2];
spi_transfer(tx, rx, 2);
Example 2
uint8_t rx[4];
spi_transfer(NULL, rx, 4);

Transfer data over SPI (full duplex).

Sends and receives data simultaneously on the SPI bus.

For read-only transfers, pass NULL for tx:

Parameters:

Name Type Description
tx const void * Pointer to transmit buffer.
rx void * Pointer to receive buffer.
len int Number of bytes.

Returns: 0 on success, negative on error.