Espressif ESP32-S2 User Manual

Chapter 2. API Reference
SPI_DEVICE_HALFDUPLEX
Transmit data before receiving it, instead of simultaneously.
SPI_DEVICE_CLK_AS_CS
Output clock on CS line if CS is active.
SPI_DEVICE_NO_DUMMY
There are timing issue when reading at high frequency (the frequency is related to whether iomux pins are used,
valid time after slave sees the clock).
• In half-duplex mode, the driver automatically inserts dummy bits before reading phase to fix the timing
issue. Set this flag to disable this feature.
• In full-duplex mode, however, the hardware cannot use dummy bits, so there is no way to prevent data
being read from getting corrupted. Set this flag to confirm that you’re going to work with output only,
or read without dummy bits at your own risk.
SPI_DEVICE_DDRCLK
SPI_TRANS_MODE_DIO
Transmit/receive data in 2-bit mode.
SPI_TRANS_MODE_QIO
Transmit/receive data in 4-bit mode.
SPI_TRANS_USE_RXDATA
Receive into rx_data member of spi_transaction_t instead into memory at rx_buffer.
SPI_TRANS_USE_TXDATA
Transmit tx_data member of spi_transaction_t instead of data at tx_buffer. Do not set tx_buffer when using
this.
SPI_TRANS_MODE_DIOQIO_ADDR
Also transmit address in mode selected by SPI_MODE_DIO/SPI_MODE_QIO.
SPI_TRANS_VARIABLE_CMD
Use the command_bits in spi_transaction_ext_t rather than default value in
spi_device_interface_config_t.
SPI_TRANS_VARIABLE_ADDR
Use the address_bits in spi_transaction_ext_t rather than default value in
spi_device_interface_config_t.
SPI_TRANS_VARIABLE_DUMMY
Use the dummy_bits in spi_transaction_ext_t rather than default value in
spi_device_interface_config_t.
SPI_TRANS_CS_KEEP_ACTIVE
Keep CS active after data transfer.
SPI_TRANS_MULTILINE_CMD
The data lines used at command phase is the same as data phase (otherwise, only one data line is used at
command phase)
SPI_TRANS_MODE_OCT
Transmit/receive data in 8-bit mode.
SPI_TRANS_MULTILINE_ADDR
The data lines used at address phase is the same as data phase (otherwise, only one data line is used at address
phase)
Type Definitions
typedef struct spi_transaction_t spi_transaction_t
typedef void (*transaction_cb_t)(spi_transaction_t *trans)
typedef struct spi_device_t *spi_device_handle_t
Handle for a device on a SPI bus.
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Release v4.4

Espressif ESP32-S2 Specifications

General

Brand	Espressif
Model	ESP32-S2
Category	Single board computers
Language	English