https://github.com/tech02-7semi/7semi_bmi270

Arduino wrapper for the Bosch BMI270 IMU (accelerometer + gyroscope) using I2C or SPI. Provides Arduino-friendly initialization, configuration, and data reading functions while using the official Bosch BMI2/BMI270 driver.
https://github.com/tech02-7semi/7semi_bmi270

accelerometer arduino bmi270 embedded esp32 gyroscope i2c imu sensor spi

Last synced: 2 months ago
JSON representation

Arduino wrapper for the Bosch BMI270 IMU (accelerometer + gyroscope) using I2C or SPI. Provides Arduino-friendly initialization, configuration, and data reading functions while using the official Bosch BMI2/BMI270 driver.

• Host: GitHub
• URL: https://github.com/tech02-7semi/7semi_bmi270
• Owner: Tech02-7semi
• License: mit
• Created: 2026-01-03T06:36:19.000Z (5 months ago)
• Default Branch: main
• Last Pushed: 2026-04-02T07:53:06.000Z (2 months ago)
• Last Synced: 2026-04-02T21:38:04.952Z (2 months ago)
• Topics: accelerometer, arduino, bmi270, embedded, esp32, gyroscope, i2c, imu, sensor, spi
• Language: C
• Homepage: https://7semi.com/imu-bmi270-accelerometer-and-gyroscope-breakout-stemma-qt-qwiic/
• Size: 159 KB
• Stars: 0
• Watchers: 0
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

          
# BMI270 7Semi Library

This repository contains basic, well-documented examples for using the Bosch BMI270 IMU with an ESP32, using the 7Semi_BMI270 library.  

**Supported interfaces:** I2C / SPI  

---

## Connection Guide

### I2C Connection (Default & Recommended)

| BMI270 Pin | ESP32 Pin | Notes             |

|------------|-----------|-----------------|

| VCC        | 3.3V      | check your board's tolerance   |

| GND        | GND       | Common ground   |

| SDA        | GPIO 21   | Can be changed  |

| SCL        | GPIO 22   | Can be changed  |

| SDO        | LOW       | Sets I2C address to 0x68 |

**I2C Address:**  

- 0x68 → SDO = LOW  

- 0x69 → SDO = HIGH  

**I2C Speed:**  

- Recommended: 400 kHz  

- Supported: up to 1 MHz  

---

### SPI Connection (Advanced)

 **Important:** BMI270 selects SPI or I2C at power-up. To force SPI mode, CS must be LOW during power-up.  

**ESP32 VSPI Wiring:**  

| BMI270 Pin | ESP32 Pin | Notes                |

|------------|-----------|--------------------|

| CS         | GPIO 5    | Must be LOW at boot |

| SCK        | GPIO 18   | VSPI clock          |

| MISO       | GPIO 19   | VSPI MISO           |

| MOSI       | GPIO 23   | VSPI MOSI           |

| VCC        | 3.3V      | Required            |

| GND        | GND       | Required            |

**SPI Configuration:**  

- Mode: SPI MODE 0  

- Init speed: ≤ 1 MHz  

- Normal speed: ≤ 10 MHz  

---

## Sensor Configuration

### Accelerometer

**Output Data Rate (ODR):**  

- BMI2_ACC_ODR_0_78HZ   (ultra low power)  

- BMI2_ACC_ODR_12_5HZ  

- BMI2_ACC_ODR_25HZ  

- BMI2_ACC_ODR_50HZ  

- BMI2_ACC_ODR_100HZ   ← recommended  

- BMI2_ACC_ODR_200HZ  

- BMI2_ACC_ODR_400HZ  

- BMI2_ACC_ODR_800HZ  

- BMI2_ACC_ODR_1600HZ  

**Measurement Range:**  

- BMI2_ACC_RANGE_2G    ← best resolution  

- BMI2_ACC_RANGE_4G  

- BMI2_ACC_RANGE_8G  

- BMI2_ACC_RANGE_16G   (large motion)  

**Bandwidth (Noise vs Latency):**  

- BMI2_ACC_OSR4_AVG1   (lowest latency)  

- BMI2_ACC_OSR2_AVG2  

- BMI2_ACC_NORMAL_AVG4 ← recommended  

- BMI2_ACC_CIC_AVG8  

- BMI2_ACC_RES_AVG16  

- BMI2_ACC_RES_AVG32  

- BMI2_ACC_RES_AVG64  

- BMI2_ACC_RES_AVG128  (lowest noise)  

---

### Gyroscope Options

**Output Data Rate (ODR):**  

- BMI2_GYR_ODR_25HZ  

- BMI2_GYR_ODR_50HZ  

- BMI2_GYR_ODR_100HZ   ← recommended  

- BMI2_GYR_ODR_200HZ  

- BMI2_GYR_ODR_400HZ  

- BMI2_GYR_ODR_800HZ  

- BMI2_GYR_ODR_1600HZ  

- BMI2_GYR_ODR_3200HZ  

**Measurement Range (deg/s):**  

- BMI2_GYR_RANGE_125  

- BMI2_GYR_RANGE_250  

- BMI2_GYR_RANGE_500  

- BMI2_GYR_RANGE_1000  

- BMI2_GYR_RANGE_2000  ← fast motion  

**Bandwidth:**  

- BMI2_GYR_OSR4_MODE   (lowest latency)  

- BMI2_GYR_OSR2_MODE  

- BMI2_GYR_NORMAL_MODE ← recommended  

---

### Recommended Default Configuration

| Sensor        | ODR   | Range       | Bandwidth      |

|---------------|-------|------------|----------------|

| Accelerometer | 100 Hz | ±2G        | NORMAL_AVG4    |

| Gyroscope     | 100 Hz | ±2000 dps  | NORMAL_MODE    |

### Output Units

| Sensor        | Unit                  |

|---------------|---------------------|

| Accelerometer | g                   |

| Gyroscope     | degrees/second (dps)|

| Temperature   | °C                  |

---

## Debug Tips

- **Wrong CHIP_ID?**  

  Expected value: 0x24. Check wiring and power.  

- **SPI not working?**  

  CS must be LOW at power-up.  

- **No data?**  

  Confirm ODR is enabled and check loop timing.  

---

## Next Steps / Advanced Features

- FIFO burst reads  

- Interrupt-driven data ready  

- Low-power mode  

- Sensor fusion (external)  

- Calibration routines  

---

## License

**MIT License** – This Arduino/C++ wrapper, examples, and documentation are released under the MIT License.  

**Bosch Sensortec Driver:**  

- This library uses the official Bosch Sensortec BMI2/BMI270 C driver, which is copyright © Bosch Sensortec GmbH and licensed under the BSD 3-Clause License.  

- Bosch license terms must be retained when redistributing Bosch source/header files.  

- This wrapper does not modify or replace Bosch’s license; it only adds Arduino integration.