The usage of hal_i2c driver is self documented in hal_i2c.h header file. Please refer to it for details.
Typically, you need to work with the following functions:
int8_t i2cTransmit(uint8_t id, const uint8_t tx[], uint8_t len);
int8_t i2cReceive(uint8_t id, uint8_t* rx, uint8_t len);If you want to use stm32 platform, you should specify LIBPERIPH_PLATFORM=stm32.
It is expected to configure the periphery in STM32CubeMX.
You should enable i2c as shown below:
If you want to use Ubuntu platform, you should specify LIBPERIPH_PLATFORM=ubuntu.
Ubuntu platform might used either for unit tests or for SITL mode.
For unit tests example based on Ubuntu implementation please check tests/periphery/test_i2c.cpp.
In SITL mode you should implement your own version of ubuntu_i2c_id and ubuntu_i2c_buffer array:
uint8_t ubuntu_i2c_id = 42;
uint8_t ubuntu_i2c_buffer[256] = {};By default, these variables have a weak attributes.
So, you can change the values of I2C in real time to emulate the real I2C in a way you want.