/* * MIT License * * Copyright (c) 2021 Joey Castillo * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "lis2dw.h" #include "watch.h" bool lis2dw_begin(void) { if (lis2dw_get_device_id() != LIS2DW_WHO_AM_I_VAL) { return false; } watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL2, LIS2DW_CTRL2_VAL_BOOT); watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL2, LIS2DW_CTRL2_VAL_SOFT_RESET); // Start at lowest possible data rate and lowest possible power mode watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1, LIS2DW_CTRL1_VAL_ODR_LOWEST | LIS2DW_CTRL1_VAL_MODE_LOW_POWER | LIS2DW_CTRL1_VAL_LPMODE_1); // Enable block data update (output registers not updated until MSB and LSB have been read) and address autoincrement watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL2, LIS2DW_CTRL2_VAL_BDU | LIS2DW_CTRL2_VAL_IF_ADD_INC); // Set range to ±2G watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL6, LIS2DW_CTRL6_VAL_RANGE_2G); return true; } uint8_t lis2dw_get_device_id(void) { return watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_WHO_AM_I); } bool lis2dw_have_new_data(void) { uint8_t retval = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_STATUS); return retval & LIS2DW_STATUS_VAL_DRDY; } lis2dw_reading lis2dw_get_raw_reading(void) { uint8_t buffer[6]; uint8_t reg = LIS2DW_REG_OUT_X_L | 0x80; // set high bit for consecutive reads lis2dw_reading retval; watch_i2c_send(LIS2DW_ADDRESS, ®, 1); watch_i2c_receive(LIS2DW_ADDRESS, (uint8_t *)&buffer, 6); retval.x = buffer[0]; retval.x |= ((uint16_t)buffer[1]) << 8; retval.y = buffer[2]; retval.y |= ((uint16_t)buffer[3]) << 8; retval.z = buffer[4]; retval.z |= ((uint16_t)buffer[5]) << 8; return retval; } lis2dw_acceleration_measurement lis2dw_get_acceleration_measurement(lis2dw_reading *out_reading) { lis2dw_reading reading = lis2dw_get_raw_reading(); uint8_t range = lis2dw_get_range(); if (out_reading != NULL) *out_reading = reading; // this bit is cribbed from Adafruit's LIS3DH driver; from their notes, the magic number below // converts from 16-bit lsb to 10-bit and divides by 1k to convert from milli-gs. // final value is raw_lsb => 10-bit lsb -> milli-gs -> gs uint8_t lsb_value = 1; if (range == LIS2DW_RANGE_2_G) lsb_value = 4; if (range == LIS2DW_RANGE_4_G) lsb_value = 8; if (range == LIS2DW_RANGE_8_G) lsb_value = 16; if (range == LIS2DW_RANGE_16_G) lsb_value = 48; lis2dw_acceleration_measurement retval; retval.x = lsb_value * ((float)reading.x / 64000.0); retval.y = lsb_value * ((float)reading.y / 64000.0); retval.z = lsb_value * ((float)reading.z / 64000.0); return retval; } void lis2dw_set_range(lis2dw_range_t range) { uint8_t val = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL6) & ~(LIS2DW_RANGE_16_G << 4); uint8_t bits = range << 4; watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL6, val | bits); } lis2dw_range_t lis2dw_get_range(void) { uint8_t retval = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL6) & (LIS2DW_RANGE_16_G << 4); retval >>= 4; return (lis2dw_range_t)retval; } void lis2dw_set_data_rate(lis2dw_data_rate_t dataRate) { uint8_t val = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & ~(0b1111 << 4); uint8_t bits = dataRate << 4; watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1, val | bits); } lis2dw_data_rate_t lis2dw_get_data_rate(void) { return watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) >> 4; } void lis2dw_set_low_power_mode(lis2dw_low_power_mode_t mode) { uint8_t val = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & ~(0b11); uint8_t bits = mode & 0b11; watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1, val | bits); } lis2dw_low_power_mode_t lis2dw_get_low_power_mode(void) { return watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & 0b11; } void lis2dw_set_low_noise_mode(bool on) { uint8_t val = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & ~(LIS2DW_CTRL6_VAL_LOW_NOISE); uint8_t bits = on ? LIS2DW_CTRL6_VAL_LOW_NOISE : 0; watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1, val | bits); } bool lis2dw_get_low_noise_mode(void) { return (watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & LIS2DW_CTRL6_VAL_LOW_NOISE) != 0; }