60 lines
1.7 KiB
Markdown
60 lines
1.7 KiB
Markdown
# LIS3DH
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A C89 driver for the 3-axis accelerometer LIS3DH. Supports both i2c and SPI.
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> ### Features
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> - FIFO
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> - HP filter
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> - 2G, 4G, 8G and 16G
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> - Low-power mode, normal mode and high-resolution mode
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> - ADC (x3) and temperature sensing
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> - Interrupt generation
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> - Free-fall detection (soon)
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> - Single-click detection
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> - Double-click detection
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> - 4D/6D orientation detection (soon)
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## Examples
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See the examples/ dir for complete code examples
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## Implementation
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This driver requires the user to provide pointers to the following abstractely named functions:
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This project has example interface code for I2C used on Raspberry Pi.
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```c
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/* initialise the "interface" */
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int init(void);
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/* read from device register `reg`, `size` amount of bytes and write them to `dst` */
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int read(uint8_t reg, uint8_t *dst, uint32_t size);
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/* write `value` to device register `reg` */
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int write(uint8_t reg, uint8_t value);
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/* sleep for `dur_us` microseconds */
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int sleep(uint32_t dur_us);
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/* deinitalise the "interface" */
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int deinit(void);
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```
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All above functions return `0` on success.
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The `init` and `deinit` pointers can both be set to `NULL` and they won't be run.
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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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```
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