Line data    Source code

       1             : /*
       2             :    This program is free software: you can redistribute it and/or modify
       3             :    it under the terms of the GNU General Public License as published by
       4             :    the Free Software Foundation, either version 3 of the License, or
       5             :    (at your option) any later version.
       6             : 
       7             :    This program is distributed in the hope that it will be useful,
       8             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
       9             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      10             :    GNU General Public License for more details.
      11             : 
      12             :    You should have received a copy of the GNU General Public License
      13             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.
      14             :  */
      15             : 
      16             : #include "AP_TemperatureSensor_TSYS03.h"
      17             : 
      18             : #if AP_TEMPERATURE_SENSOR_TSYS03_ENABLED
      19             : #include <utility>
      20             : #include <stdio.h>
      21             : #include <AP_HAL/I2CDevice.h>
      22             : #include <AP_Math/AP_Math.h>
      23             : 
      24             : #include <GCS_MAVLink/GCS.h>
      25             : 
      26             : #ifndef AP_TEMPERATURE_SENSOR_TSYS03_ENFORCE_KNOWN_VALID_I2C_ADDRESS
      27             : #define AP_TEMPERATURE_SENSOR_TSYS03_ENFORCE_KNOWN_VALID_I2C_ADDRESS 1
      28             : #endif
      29             : 
      30             : extern const AP_HAL::HAL &hal;
      31             : 
      32             : static const uint8_t TSYS03_CMD_RESET       = 0x1E;
      33             : static const uint8_t TSYS03_CMD_CONVERT     = 0x46;
      34             : static const uint8_t TSYS03_CMD_READ_ADC    = 0x00;
      35             : 
      36           0 : void AP_TemperatureSensor_TSYS03::init()
      37             : {
      38           0 :     constexpr char name[] = "TSYS03";
      39             :     (void)name;  // sometimes this is unused (e.g. HAL_GCS_ENABLED false)
      40             : 
      41             : #if AP_TEMPERATURE_SENSOR_TSYS03_ENFORCE_KNOWN_VALID_I2C_ADDRESS
      42             :     // I2C Address: Default to using TSYS03_ADDR_CSB0 & Check I2C Address is Correct
      43           0 :     if ((_params.bus_address != TSYS03_ADDR_CSB0) ) {
      44           0 :         GCS_SEND_TEXT(MAV_SEVERITY_WARNING, "%s wrong I2C addr of 0x%2X, setting to 0x%2X", name, (unsigned)_params.bus_address.get(), (unsigned)TSYS03_ADDR_CSB0);
      45           0 :         _params.bus_address.set(TSYS03_ADDR_CSB0);
      46             :     }
      47             : #endif
      48             : 
      49           0 :     _dev = hal.i2c_mgr->get_device_ptr(_params.bus, _params.bus_address);
      50           0 :     if (!_dev) {
      51           0 :         GCS_SEND_TEXT(MAV_SEVERITY_WARNING, "%s device is null!", name);
      52           0 :         return;
      53             :     }
      54             : 
      55           0 :     WITH_SEMAPHORE(_dev->get_semaphore());
      56             : 
      57           0 :     _dev->set_retries(10);
      58             : 
      59             :     // reset
      60           0 :     if (!_dev->transfer(&TSYS03_CMD_RESET, 1, nullptr, 0)) {
      61           0 :         GCS_SEND_TEXT(MAV_SEVERITY_WARNING, "%s reset failed", name);
      62           0 :         return;
      63             :     }
      64             : 
      65           0 :     hal.scheduler->delay(4);
      66             : 
      67           0 :     start_next_sample();
      68             : 
      69             :     // lower retries for run
      70           0 :     _dev->set_retries(3);
      71             : 
      72             :     /* Request 20Hz update */
      73             :     // Max conversion time is 9.04 ms
      74           0 :     _dev->register_periodic_callback(50 * AP_USEC_PER_MSEC,
      75             :                                      FUNCTOR_BIND_MEMBER(&AP_TemperatureSensor_TSYS03::_timer, void));
      76           0 : }
      77             : 
      78           0 : uint16_t AP_TemperatureSensor_TSYS03::read_adc() const
      79             : {
      80             :     uint8_t val[3];
      81           0 :     if (!_dev->transfer(&TSYS03_CMD_READ_ADC, 1, val, 3)) {
      82           0 :         return 0;
      83             :     }
      84             : 
      85             :     // ensure crc is correct:
      86           0 :     uint8_t expected_crc = 0;
      87           0 :     for (uint8_t i=0; i<2; i++) {
      88           0 :         expected_crc = crc8_dvb(expected_crc, val[i], 0x31);
      89             :     }
      90           0 :     if (expected_crc != val[2]) {
      91           0 :         return 0;
      92             :     }
      93             : 
      94           0 :     return UINT16_VALUE(val[0],val[1]);
      95             : }
      96             : 
      97           0 : void AP_TemperatureSensor_TSYS03::_timer(void)
      98             : {
      99           0 :     const uint16_t adc = read_adc();
     100             : 
     101           0 :     if (adc != 0) {
     102           0 :         const float temp = calculate(adc);
     103           0 :         set_temperature(temp);
     104             :     }
     105             : 
     106           0 :     start_next_sample();
     107           0 : }
     108             : 
     109           0 : void AP_TemperatureSensor_TSYS03::start_next_sample()
     110             : {
     111           0 :     _dev->transfer(&TSYS03_CMD_CONVERT, 1, nullptr, 0);
     112           0 : }
     113             : 
     114           0 : float AP_TemperatureSensor_TSYS03::calculate(const uint16_t adc) const
     115             : {
     116           0 :     const float temperature = -40.0 + adc * 165 / (powf(2, 16) - 1.0);
     117             : 
     118           0 :     return temperature;
     119             : }
     120             : 
     121             : #endif // AP_TEMPERATURE_SENSOR_TSYS03_ENABLED