STM32GENERIC/tools/documentation/mkdocs/spi.md

SPI

To use the hardware SPI, include it in your code:

#include "SPI.h"

The first SPI object is explicitly created, and is connected to the SPI1 instance.

Please check your board documentation to see which pins is SPI connected to by default.

To use additional SPI, use the constructors to create your object, or the stm32SetInstance() method.

SPIClass(SPI_TypeDef *instance)

Create a SPI object that is connected to the instance, on the default mosi/miso/sck. To avoid confusion, it is better to use the constructor below with implicit pins.

SPIClass(SPI_TypeDef *instance, uint8_t mosi, uint8_t miso, uint8_t sck)

Create a SPI object that is connected to the instance, on the specified mosi/miso/sck pins.

Please check the documentation of the chip to see which pins can be used.

Example: set up SPI2

SPIClass SPI_2(SPI2, mosi, iso, sck);
void setup() {
    SPI_2.begin();
}

begin()

Enables SPI on the pins

end()

Disables SPI on the pins

beginTransaction(SPISettings settings);

Initializes SPI with the provided SPISettings mySetting(speedMaximum, dataOrder, dataMode) parameters.

Parameter	Description
speedMaximum	The maximum speed requested
dataOrder	MSBFIRST, LSBFIRST
dataMode	SPI_MODE0, SPI_MODE1, SPI_MODE2, or SPI_MODE3

Example:

SPI.beginTransaction(SPISettings(16000000, MSBFIRST, SPI_MODE0));

TODO disable interrupt in pin if usingInterrupt was used

endTransaction();

TODO enable interrupt in pin if usingInterrupt was used

transfer(...);

TODO write doc

transfer16(...);

TODO write doc

transfer(...);

TODO write doc

usingInterrupt();

TODO not yet implemented

transfer(...);

TODO write doc

stm32SetMOSI(uint8_t pin);

Set the MOSI pin used by this SPI.

This method must be called before begin()!

stm32SetMISO(uint8_t pin);

Set the alternative MISO pin used by this SPI.

This method must be called before begin()!

stm32SetSCK(uint8_t pin);

Set the alternative SCK pin used by this SPI.

This method must be called before begin()!

stm32SetInstance(SPI_TypeDef *instance);

Set the alternative SPI instance (SPI1/SPI2/...) used by this object.

This method must be called before begin()!

Example: If you want to use a library that has hardcoded SPI in it, but you want to use SPI2:

#include "SPI.h"

void setup() {
    SPI.stm32SetInstance(SPI2);
    SPI.stm32SetMOSI(mosi);
    SPI.stm32SetMISO(miso);
    SPI.stm32SetSCK(sck);
    ...
    library.begin();
}