git.gag.com Git - fw/altos/blob - src/kernel/ao_flight_nano.c

   1 /*
   2  * Copyright © 2011 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  17  */
  18
  19 #include "ao.h"
  20
  21 /* Main flight thread. */
  22
  23 enum ao_flight_state    ao_flight_state;        /* current flight state */
  24 uint16_t                ao_launch_tick;         /* time of launch detect */
  25
  26 /*
  27  * track min/max data over a long interval to detect
  28  * resting
  29  */
  30 uint16_t                ao_interval_end;
  31 alt_t                   ao_interval_min_height;
  32 alt_t                   ao_interval_max_height;
  33
  34 uint8_t                 ao_flight_force_idle;
  35
  36 /* Landing is detected by getting constant readings from both pressure and accelerometer
  37  * for a fairly long time (AO_INTERVAL_TICKS)
  38  */
  39 #define AO_INTERVAL_TICKS       AO_SEC_TO_TICKS(5)
  40
  41 static void
  42 ao_flight_nano(void)
  43 {
  44         ao_sample_init();
  45         ao_flight_state = ao_flight_startup;
  46
  47         for (;;) {
  48                 /*
  49                  * Process ADC samples, just looping
  50                  * until the sensors are calibrated.
  51                  */
  52                 if (!ao_sample())
  53                         continue;
  54
  55                 switch (ao_flight_state) {
  56                 case ao_flight_startup:
  57                         if (ao_flight_force_idle) {
  58                                 /* Set idle mode */
  59                                 ao_flight_state = ao_flight_idle;
  60                         } else {
  61                                 ao_flight_state = ao_flight_pad;
  62                                 /* Disable packet mode in pad state */
  63                                 ao_packet_slave_stop();
  64
  65                                 /* Turn on telemetry system */
  66                                 ao_rdf_set(1);
  67                                 ao_telemetry_set_interval(AO_TELEMETRY_INTERVAL_PAD);
  68                         }
  69                         /* signal successful initialization by turning off the LED */
  70                         ao_led_off(AO_LED_RED);
  71
  72                         /* wakeup threads due to state change */
  73                         ao_wakeup(&ao_flight_state);
  74                         break;
  75                 case ao_flight_pad:
  76                         if (ao_height> AO_M_TO_HEIGHT(20)) {
  77                                 ao_flight_state = ao_flight_drogue;
  78                                 ao_launch_tick = ao_sample_tick;
  79
  80                                 /* start logging data */
  81                                 ao_log_start();
  82
  83                                 ao_wakeup(&ao_flight_state);
  84                         }
  85                         break;
  86                 case ao_flight_drogue:
  87                         /* drogue/main to land:
  88                          *
  89                          * barometer: altitude stable
  90                          */
  91
  92                         if (ao_height < ao_interval_min_height)
  93                                 ao_interval_min_height = ao_height;
  94                         if (ao_height > ao_interval_max_height)
  95                                 ao_interval_max_height = ao_height;
  96
  97                         if ((int16_t) (ao_sample_tick - ao_interval_end) >= 0) {
  98                                 if (ao_interval_max_height - ao_interval_min_height < AO_M_TO_HEIGHT(5))
  99                                 {
 100                                         ao_flight_state = ao_flight_landed;
 101
 102                                         /* turn off the ADC capture */
 103                                         ao_timer_set_adc_interval(0);
 104                                         ao_wakeup(&ao_flight_state);
 105                                 }
 106                                 ao_interval_min_height = ao_interval_max_height = ao_height;
 107                                 ao_interval_end = ao_sample_tick + AO_INTERVAL_TICKS;
 108                         }
 109                         break;
 110                 }
 111         }
 112 }
 113
 114 static struct ao_task   flight_task;
 115
 116 void
 117 ao_flight_nano_init(void)
 118 {
 119         ao_flight_state = ao_flight_startup;
 120         ao_add_task(&flight_task, ao_flight_nano, "flight");
 121 }