LIS3DH / STMicroelectronics / MEMS motion sensor, 3-axis accelerometer library
LIS3DH.cpp
- Committer:
- kenjiArai
- Date:
- 2014-12-07
- Revision:
- 2:cc943f8d76a2
- Parent:
- 1:d4d569952436
- Child:
- 3:de2cf61c0a58
File content as of revision 2:cc943f8d76a2:
/* * mbed library program * LIS3DH MEMS motion sensor: 3-axis "nano" accelerometer, made by STMicroelectronics * http://www.st-japan.co.jp/web/jp/catalog/sense_power/FM89/SC444/PF250725 * * Copyright (c) 2014 Kenji Arai / JH1PJL * http://www.page.sannet.ne.jp/kenjia/index.html * http://mbed.org/users/kenjiArai/ * Created: July 14th, 2014 * Revised: September 7th, 2014 * * 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 "LIS3DH.h" LIS3DH::LIS3DH (PinName p_sda, PinName p_scl, uint8_t addr, uint8_t data_rate, uint8_t fullscale) : i2c(p_sda, p_scl) { initialize (addr, data_rate, fullscale); } LIS3DH::LIS3DH (I2C& p_i2c, uint8_t addr, uint8_t data_rate, uint8_t fullscale) : i2c(p_i2c) { i2c.frequency(400000); initialize (addr, data_rate, fullscale); } void LIS3DH::initialize (uint8_t addr, uint8_t data_rate, uint8_t fullscale) { // Check acc is available of not acc_addr = addr; dbf[0] = LIS3DH_WHO_AM_I; i2c.write(acc_addr, dbf, 1); i2c.read(acc_addr, dbf, 1); if (dbf[0] == I_AM_LIS3DH){ acc_ready = 1; } else { acc_ready = 0; return; // acc chip is NOT on I2C line then terminate } // Reg.1 dbf[0] = LIS3DH_CTRL_REG1; dbf[1] = 0x07; dbf[1] |= data_rate << 4; i2c.write(acc_addr, dbf, 2); // Reg.4 dbf[0] = LIS3DH_CTRL_REG4; dbf[1] = 0x08; // High resolution dbf[1] |= fullscale << 4; i2c.write(acc_addr, dbf, 2); switch (fullscale){ case LIS3DH_FS_2G: fs_factor = LIS3DH_SENSITIVITY_2G; break; case LIS3DH_FS_4G: fs_factor = LIS3DH_SENSITIVITY_4G; break; case LIS3DH_FS_8G: fs_factor = LIS3DH_SENSITIVITY_8G; break; case LIS3DH_FS_16G: fs_factor = LIS3DH_SENSITIVITY_16G; break; default: ; } } void LIS3DH::read_reg_data(char *data) { // X,Y & Z // manual said that // In order to read multiple bytes, it is necessary to assert the most significant bit // of the subaddress field. // In other words, SUB(7) must be equal to ‘1’ while SUB(6-0) represents the address // of the first register to be read. dbf[0] = LIS3DH_OUT_X_L | 0x80; i2c.write(acc_addr, dbf, 1); i2c.read(acc_addr, data, 6); } void LIS3DH::read_mg_data(float *dt) { char data[6]; if (acc_ready == 0){ dt[0] = 0; dt[1] = 0; dt[2] = 0; return; } read_reg_data(data); // change data type dt[0] = float(short((data[1] << 8) | data[0])) * fs_factor / 15; dt[1] = float(short((data[3] << 8) | data[2])) * fs_factor / 15; dt[2] = float(short((data[5] << 8) | data[4])) * fs_factor / 15; } void LIS3DH::read_data(float *dt) { char data[6]; if (acc_ready == 0){ dt[0] = 0; dt[1] = 0; dt[2] = 0; return; } read_reg_data(data); // change data type dt[0] = float(short((data[1] << 8) | data[0])) * fs_factor / 15 * GRAVITY; dt[1] = float(short((data[3] << 8) | data[2])) * fs_factor / 15 * GRAVITY; dt[2] = float(short((data[5] << 8) | data[4])) * fs_factor / 15 * GRAVITY; } uint8_t LIS3DH::read_id() { dbf[0] = LIS3DH_WHO_AM_I; i2c.write(acc_addr, dbf, 1); i2c.read(acc_addr, dbf, 1); return (uint8_t)dbf[0]; } uint8_t LIS3DH::data_ready() { if (acc_ready == 1){ dbf[0] = LIS3DH_STATUS_REG_AUX; i2c.write(acc_addr, dbf, 1); i2c.read(acc_addr, dbf, 1); if (!(dbf[0] & 0x01)){ return 0; } } return 1; } void LIS3DH::frequency(int hz) { i2c.frequency(hz); } uint8_t LIS3DH::read_reg(uint8_t addr) { if (acc_ready == 1){ dbf[0] = addr; i2c.write(acc_addr, dbf, 1); i2c.read(acc_addr, dbf, 1); } else { dbf[0] = 0xff; } return (uint8_t)dbf[0]; } void LIS3DH::write_reg(uint8_t addr, uint8_t data) { if (acc_ready == 1){ dbf[0] = addr; dbf[1] = data; i2c.write(acc_addr, dbf, 2); } }