STM32 Scan I²C bus
Revision as of 03:41, 4 June 2021 by Lth (talk | contribs) (Created page with "Category:STM32Category:STM32 DevelopmentCategory:STM32CubeMXCategory:STM32CubeIdeCategory:STM32 HALCategory:I2C{{metadesc|How to scan an I2C bus using...")
Scanning an I2C bus using HAL is really simple. First configure I2C in Stm32CubeMX:
Once the I2C has been configured, scanning the bus for slaves become a simple matter:
// Go through all possible i2c addresses
for (uint8_t i = 0; i < 128; i++) {
if (HAL_I2C_IsDeviceReady(&hi2c1, (uint16_t)(i<<1), 3, 5) == HAL_OK) {
// We got an ack
printf("%2x ", i);
} else {
printf("-- ");
}
if (i > 0 && (i + 1) % 16 == 0) printf("\n");
}
printf("\n");
The HAL_I2C_IsDeviceReady will return HAL_OK if it receives an ACK or an error if not.
Output from above could be:
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 1e -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 53 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 68 -- -- -- -- -- -- -- -- -- -- -- -- -- -- 77 -- -- -- -- -- -- -- --