See the License for the specific language governing permissions and
limitations under the License.
*/
#include "ch.h"
#include "hal.h"
/*
* Timing values are taken from the RM except the PRESC set to 9 because
* the input clock is 72MHz.
* The timings are critical, please always refer to the STM32 Reference
* Manual before attempting changes.
*/
#if 0
static const I2CConfig i2cconfig = {
STM32_TIMINGR_PRESC(8U) | /* 72MHz/9 = 8MHz I2CCLK. */
STM32_TIMINGR_SCLDEL(3U) | STM32_TIMINGR_SDADEL(3U) |
STM32_TIMINGR_SCLH(3U) | STM32_TIMINGR_SCLL(9U),
0,
0
};
#endif
static const I2CConfig i2cconfig = {
STM32_TIMINGR_PRESC(15U) |
STM32_TIMINGR_SCLDEL(4U) | STM32_TIMINGR_SDADEL(2U) |
STM32_TIMINGR_SCLH(15U) | STM32_TIMINGR_SCLL(21U),
0,
0
};
/*
* can be changed.
* Please ensure that HAL_USE_I2C is TRUE in the halconf.h file and that
* STM32_I2C_USE_I2C1 is TRUE in the mcuconf.h file. Pins B6 and B7 are used
* but using any other I2C pins should be trivial.
*/
#include "i2c_master.h"
#include <string.h>
#include <hal.h>
static uint8_t i2c_address;
// This configures the I2C clock to 400Mhz assuming a 72Mhz clock
// For more info : https://www.st.com/en/embedded-software/stsw-stm32126.html
static const I2CConfig i2cconfig = {
STM32_TIMINGR_PRESC(15U) |
STM32_TIMINGR_SCLDEL(4U) | STM32_TIMINGR_SDADEL(2U) |
STM32_TIMINGR_SCLH(15U) | STM32_TIMINGR_SCLL(21U),
0,
0
};
void i2c_init(void)
{
palSetGroupMode(GPIOB, GPIOB_PIN6 | GPIOB_PIN7, 0, PAL_MODE_INPUT); // Try releasing special pins for a short time
chThdSleepMilliseconds(10);
palSetPadMode(GPIOB, 6, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
palSetPadMode(GPIOB, 7, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
//i2cInit(); //This is invoked by halInit() so no need to redo it.
