91 lines
2.8 KiB
Markdown
91 lines
2.8 KiB
Markdown
# LIS3DH
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A C89 driver for the 3-axis accelerometer LIS3DH by ST. Supports both i2c and SPI.
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> ### Features
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> - FIFO of varying watermark level, up to 32
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> - HP filter
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> - 2G, 4G, 8G and 16G
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> - All power modes
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> - Interrupt generation (soon)
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> - Free-fall detection (soon)
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> - Single and double click detection (soon)
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> - 4D/6D orientation detection (soon)
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FIFO output example
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```
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$ ./lis3dh
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x: 0.5320, y: -0.8800, z: -0.0600 mag: 1.0301
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x: 0.5440, y: -0.8680, z: -0.0760 mag: 1.0272
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0760 mag: 1.0306
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x: 0.5440, y: -0.8720, z: -0.0720 mag: 1.0303
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0720 mag: 1.0392
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x: 0.5480, y: -0.8800, z: -0.0800 mag: 1.0398
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x: 0.5480, y: -0.8960, z: -0.0960 mag: 1.0547
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```
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> ### Notes
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> FIFO is always and only 10-bit
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### Noise at 2G
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### Noise at 4G
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### Noise at 8G
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### Noise at 16G
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## Using i2c on STM32
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Simple example code
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```c
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#define LIS3DH_I2C_ADDR 0x18
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int i2c_write(uint8_t reg, uint8_t value) {
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uint8_t buf[2] = { reg, value };
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HAL_I2C_Master_Transmit(&hi2c2, LIS3DH_I2C_ADDR << 1, buf, 2, HAL_MAX_DELAY);
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return 0;
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}
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int i2c_read(uint8_t reg, uint8_t *dst, uint32_t size) {
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uint8_t send[2] = { reg, 0x00 };
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HAL_I2C_Master_Transmit(&hi2c2, LIS3DH_I2C_ADDR << 1, send, 2, HAL_MAX_DELAY);
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HAL_I2C_Master_Receive(&hi2c2, LIS3DH_I2C_ADDR << 1, dst, size, HAL_MAX_DELAY);
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return 0;
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}
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``` |