ardupilot/libraries/AP_InertialSensor/AP_InertialSensor_L3G4200D.cpp

347 lines
13 KiB
C++

/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
This is an INS driver for the combination L3G4200D gyro and ADXL345 accelerometer.
This combination is available as a cheap 10DOF sensor on ebay
This sensor driver is an example only - it should not be used in any
serious autopilot as the latencies on I2C prevent good timing at
high sample rates. It is useful when doing an initial port of
ardupilot to a board where only I2C is available, and a cheap sensor
can be used.
Datasheets:
ADXL345 Accelerometer http://www.analog.com/static/imported-files/data_sheets/ADXL345.pdf
L3G4200D gyro http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/CD00265057.pdf
*/
#include <AP_HAL.h>
#if CONFIG_HAL_BOARD == HAL_BOARD_LINUX
#include <AP_Math.h>
#include "AP_InertialSensor_L3G4200D.h"
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <sys/time.h>
#include <sched.h>
#include <linux/rtc.h>
#include <stdio.h>
#include <time.h>
#include <math.h>
#include <sched.h>
#include <linux/rtc.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdbool.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/mman.h>
const extern AP_HAL::HAL& hal;
///////
/// Accelerometer ADXL345 register definitions
#define ADXL345_ACCELEROMETER_ADDRESS 0x53
#define ADXL345_ACCELEROMETER_XL345_DEVID 0xe5
#define ADXL345_ACCELEROMETER_ADXLREG_BW_RATE 0x2c
#define ADXL345_ACCELEROMETER_ADXLREG_POWER_CTL 0x2d
#define ADXL345_ACCELEROMETER_ADXLREG_DATA_FORMAT 0x31
#define ADXL345_ACCELEROMETER_ADXLREG_DEVID 0x00
#define ADXL345_ACCELEROMETER_ADXLREG_DATAX0 0x32
#define ADXL345_ACCELEROMETER_ADXLREG_FIFO_CTL 0x38
#define ADXL345_ACCELEROMETER_ADXLREG_FIFO_CTL_STREAM 0x9F
#define ADXL345_ACCELEROMETER_ADXLREG_FIFO_STATUS 0x39
// ADXL345 accelerometer scaling
// Result will be scaled to 1m/s/s
// ADXL345 in Full resolution mode (any g scaling) is 256 counts/g, so scale by 9.81/256 = 0.038320312
#define ADXL345_ACCELEROMETER_SCALE_M_S (GRAVITY_MSS / 256.0f)
/// Gyro ITG3205 register definitions
#define L3G4200D_I2C_ADDRESS 0x69
#define L3G4200D_REG_WHO_AM_I 0x0f
#define L3G4200D_REG_WHO_AM_I_VALUE 0xd3
#define L3G4200D_REG_CTRL_REG1 0x20
#define L3G4200D_REG_CTRL_REG1_DRBW_800_110 0xf0
#define L3G4200D_REG_CTRL_REG1_PD 0x08
#define L3G4200D_REG_CTRL_REG1_XYZ_ENABLE 0x07
#define L3G4200D_REG_CTRL_REG4 0x23
#define L3G4200D_REG_CTRL_REG4_FS_2000 0x30
#define L3G4200D_REG_CTRL_REG5 0x24
#define L3G4200D_REG_CTRL_REG5_FIFO_EN 0x40
#define L3G4200D_REG_FIFO_CTL 0x2e
#define L3G4200D_REG_FIFO_CTL_STREAM 0x40
#define L3G4200D_REG_FIFO_SRC 0x2f
#define L3G4200D_REG_FIFO_SRC_ENTRIES_MASK 0x1f
#define L3G4200D_REG_FIFO_SRC_EMPTY 0x20
#define L3G4200D_REG_FIFO_SRC_OVERRUN 0x40
#define L3G4200D_REG_XL 0x28
// this bit is ORd into the register to enable auto-increment mode
#define L3G4200D_REG_AUTO_INCREMENT 0x80
// L3G4200D Gyroscope scaling
// running at 2000 DPS full range, 16 bit signed data, datasheet
// specifies 70 mdps per bit
#define L3G4200D_GYRO_SCALE_R_S (DEG_TO_RAD * 70.0f * 0.001f)
// constructor
AP_InertialSensor_L3G4200D::AP_InertialSensor_L3G4200D(AP_InertialSensor &imu) :
AP_InertialSensor_Backend(imu),
_have_gyro_sample(false),
_have_accel_sample(false),
_accel_filter_x(800, 10),
_accel_filter_y(800, 10),
_accel_filter_z(800, 10),
_gyro_filter_x(800, 10),
_gyro_filter_y(800, 10),
_gyro_filter_z(800, 10)
{}
bool AP_InertialSensor_L3G4200D::_init_sensor(void)
{
_default_filter_hz = _default_filter();
// get pointer to i2c bus semaphore
AP_HAL::Semaphore* i2c_sem = hal.i2c->get_semaphore();
// take i2c bus sempahore
if (!i2c_sem->take(HAL_SEMAPHORE_BLOCK_FOREVER))
return false;
// Init the accelerometer
uint8_t data = 0;
hal.i2c->readRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_DEVID, &data);
if (data != ADXL345_ACCELEROMETER_XL345_DEVID) {
hal.scheduler->panic(PSTR("AP_InertialSensor_L3G4200D: could not find ADXL345 accelerometer sensor"));
}
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_POWER_CTL, 0x00);
hal.scheduler->delay(5);
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_POWER_CTL, 0xff);
hal.scheduler->delay(5);
// Measure mode:
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_POWER_CTL, 0x08);
hal.scheduler->delay(5);
// Full resolution, 8g:
// Caution, this must agree with ADXL345_ACCELEROMETER_SCALE_1G
// In full resoution mode, the scale factor need not change
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_DATA_FORMAT, 0x08);
hal.scheduler->delay(5);
// Normal power, 800Hz Output Data Rate, 400Hz bandwidth:
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS, ADXL345_ACCELEROMETER_ADXLREG_BW_RATE, 0x0d);
hal.scheduler->delay(5);
// enable FIFO in stream mode. This will allow us to read the accelerometers much less frequently
hal.i2c->writeRegister(ADXL345_ACCELEROMETER_ADDRESS,
ADXL345_ACCELEROMETER_ADXLREG_FIFO_CTL,
ADXL345_ACCELEROMETER_ADXLREG_FIFO_CTL_STREAM);
// Init the Gyro
// Expect to read the right 'WHO_AM_I' value
hal.i2c->readRegister(L3G4200D_I2C_ADDRESS, L3G4200D_REG_WHO_AM_I, &data);
if (data != L3G4200D_REG_WHO_AM_I_VALUE)
hal.scheduler->panic(PSTR("AP_InertialSensor_L3G4200D: could not find L3G4200D gyro sensor"));
// setup for 800Hz sampling with 110Hz filter
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_CTRL_REG1,
L3G4200D_REG_CTRL_REG1_DRBW_800_110 |
L3G4200D_REG_CTRL_REG1_PD |
L3G4200D_REG_CTRL_REG1_XYZ_ENABLE);
hal.scheduler->delay(1);
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_CTRL_REG1,
L3G4200D_REG_CTRL_REG1_DRBW_800_110 |
L3G4200D_REG_CTRL_REG1_PD |
L3G4200D_REG_CTRL_REG1_XYZ_ENABLE);
hal.scheduler->delay(1);
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_CTRL_REG1,
L3G4200D_REG_CTRL_REG1_DRBW_800_110 |
L3G4200D_REG_CTRL_REG1_PD |
L3G4200D_REG_CTRL_REG1_XYZ_ENABLE);
hal.scheduler->delay(1);
// setup for 2000 degrees/sec full range
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_CTRL_REG4,
L3G4200D_REG_CTRL_REG4_FS_2000);
hal.scheduler->delay(1);
// enable FIFO
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_CTRL_REG5,
L3G4200D_REG_CTRL_REG5_FIFO_EN);
hal.scheduler->delay(1);
// enable FIFO in stream mode. This will allow us to read the gyros much less frequently
hal.i2c->writeRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_FIFO_CTL,
L3G4200D_REG_FIFO_CTL_STREAM);
hal.scheduler->delay(1);
// Set up the filter desired
_set_filter_frequency(_imu.get_filter());
// give back i2c semaphore
i2c_sem->give();
// start the timer process to read samples
hal.scheduler->register_timer_process(AP_HAL_MEMBERPROC(&AP_InertialSensor_L3G4200D::_accumulate));
_gyro_instance = _imu.register_gyro();
_accel_instance = _imu.register_accel();
_product_id = AP_PRODUCT_ID_L3G4200D;
return true;
}
/*
set the filter frequency
*/
void AP_InertialSensor_L3G4200D::_set_filter_frequency(uint8_t filter_hz)
{
if (filter_hz == 0)
filter_hz = _default_filter_hz;
_accel_filter_x.set_cutoff_frequency(800, filter_hz);
_accel_filter_y.set_cutoff_frequency(800, filter_hz);
_accel_filter_z.set_cutoff_frequency(800, filter_hz);
_gyro_filter_x.set_cutoff_frequency(800, filter_hz);
_gyro_filter_y.set_cutoff_frequency(800, filter_hz);
_gyro_filter_z.set_cutoff_frequency(800, filter_hz);
}
/*
copy filtered data to the frontend
*/
bool AP_InertialSensor_L3G4200D::update(void)
{
Vector3f accel, gyro;
hal.scheduler->suspend_timer_procs();
accel = _accel_filtered;
gyro = _gyro_filtered;
_have_gyro_sample = false;
_have_accel_sample = false;
hal.scheduler->resume_timer_procs();
// Adjust for chip scaling to get m/s/s
accel *= ADXL345_ACCELEROMETER_SCALE_M_S;
_rotate_and_offset_accel(_accel_instance, accel);
// Adjust for chip scaling to get radians/sec
gyro *= L3G4200D_GYRO_SCALE_R_S;
_rotate_and_offset_gyro(_gyro_instance, gyro);
if (_last_filter_hz != _imu.get_filter()) {
_set_filter_frequency(_imu.get_filter());
_last_filter_hz = _imu.get_filter();
}
return true;
}
// Accumulate values from accels and gyros
void AP_InertialSensor_L3G4200D::_accumulate(void)
{
// get pointer to i2c bus semaphore
AP_HAL::Semaphore* i2c_sem = hal.i2c->get_semaphore();
// take i2c bus sempahore
if (!i2c_sem->take_nonblocking())
return;
uint8_t num_samples_available;
uint8_t fifo_status = 0;
// Read gyro FIFO status
fifo_status = 0;
hal.i2c->readRegister(L3G4200D_I2C_ADDRESS,
L3G4200D_REG_FIFO_SRC,
&fifo_status);
if (fifo_status & L3G4200D_REG_FIFO_SRC_OVERRUN) {
// FIFO is full
num_samples_available = 32;
} else if (fifo_status & L3G4200D_REG_FIFO_SRC_EMPTY) {
// FIFO is empty
num_samples_available = 0;
} else {
// FIFO is partly full
num_samples_available = fifo_status & L3G4200D_REG_FIFO_SRC_ENTRIES_MASK;
}
if (num_samples_available > 0) {
// read all the entries in one go, using AUTO_INCREMENT. This saves a lot of time on I2C setup
int16_t buffer[num_samples_available][3];
if (hal.i2c->readRegisters(L3G4200D_I2C_ADDRESS, L3G4200D_REG_XL | L3G4200D_REG_AUTO_INCREMENT,
sizeof(buffer), (uint8_t *)&buffer[0][0]) == 0) {
for (uint8_t i=0; i<num_samples_available; i++) {
_gyro_filtered = Vector3f(_gyro_filter_x.apply(buffer[i][0]),
_gyro_filter_y.apply(-buffer[i][1]),
_gyro_filter_z.apply(-buffer[i][2]));
_have_gyro_sample = true;
}
}
}
// Read accelerometer FIFO to find out how many samples are available
hal.i2c->readRegister(ADXL345_ACCELEROMETER_ADDRESS,
ADXL345_ACCELEROMETER_ADXLREG_FIFO_STATUS,
&fifo_status);
num_samples_available = fifo_status & 0x3F;
// read the samples and apply the filter
if (num_samples_available > 0) {
int16_t buffer[num_samples_available][3];
if (hal.i2c->readRegistersMultiple(ADXL345_ACCELEROMETER_ADDRESS,
ADXL345_ACCELEROMETER_ADXLREG_DATAX0,
sizeof(buffer[0]), num_samples_available,
(uint8_t *)&buffer[0][0]) == 0) {
for (uint8_t i=0; i<num_samples_available; i++) {
_accel_filtered = Vector3f(_accel_filter_x.apply(buffer[i][0]),
_accel_filter_y.apply(-buffer[i][1]),
_accel_filter_z.apply(-buffer[i][2]));
_have_accel_sample = true;
}
}
}
// give back i2c semaphore
i2c_sem->give();
}
#endif // CONFIG_HAL_BOARD