/* 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 . */ #include "AP_RangeFinder_LightWareI2C.h" #include #include #include extern const AP_HAL::HAL& hal; /* The constructor also initializes the rangefinder. Note that this constructor is not called until detect() returns true, so we already know that we should setup the rangefinder */ AP_RangeFinder_LightWareI2C::AP_RangeFinder_LightWareI2C(RangeFinder &_ranger, uint8_t instance, RangeFinder::RangeFinder_State &_state, AP_HAL::OwnPtr dev) : AP_RangeFinder_Backend(_ranger, instance, _state) , _dev(std::move(dev)) {} /* detect if a Lightware rangefinder is connected. We'll detect by trying to take a reading on I2C. If we get a result the sensor is there. */ AP_RangeFinder_Backend *AP_RangeFinder_LightWareI2C::detect(RangeFinder &_ranger, uint8_t instance, RangeFinder::RangeFinder_State &_state, AP_HAL::OwnPtr dev) { AP_RangeFinder_LightWareI2C *sensor = new AP_RangeFinder_LightWareI2C(_ranger, instance, _state, std::move(dev)); if (!sensor) { delete sensor; return nullptr; } if (sensor->_dev->get_semaphore()->take(0)) { uint16_t reading_cm; if (!sensor->get_reading(reading_cm)) { sensor->_dev->get_semaphore()->give(); delete sensor; return nullptr; } sensor->_dev->get_semaphore()->give(); } sensor->init(); return sensor; } void AP_RangeFinder_LightWareI2C::init() { // call timer() at 20Hz _dev->register_periodic_callback(50000, FUNCTOR_BIND_MEMBER(&AP_RangeFinder_LightWareI2C::timer, bool)); } // read - return last value measured by sensor bool AP_RangeFinder_LightWareI2C::get_reading(uint16_t &reading_cm) { be16_t val; if (ranger._address[state.instance] == 0) { return false; } // read the high and low byte distance registers bool ret = _dev->read((uint8_t *) &val, sizeof(val)); if (ret) { // combine results into distance reading_cm = be16toh(val); } return ret; } /* update the state of the sensor */ void AP_RangeFinder_LightWareI2C::update(void) { // nothing to do - its all done in the timer() } bool AP_RangeFinder_LightWareI2C::timer(void) { if (get_reading(state.distance_cm)) { // update range_valid state based on distance measured update_status(); } else { set_status(RangeFinder::RangeFinder_NoData); } return true; }