2 * Copyright © 2012 Keith Packard <keithp@keithp.com>
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; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
19 #include <ao_ms5607.h>
20 #include <ao_log_micro.h>
22 static struct ao_ms5607_sample sample;
23 static struct ao_ms5607_value value;
26 static uint32_t pa_sum;
27 static uint32_t pa_avg;
28 static int32_t pa_diff;
29 static uint32_t pa_ground;
30 static uint32_t pa_min;
31 static uint32_t pa_interval_min, pa_interval_max;
32 static alt_t ground_alt, max_alt;
38 ao_ms5607_sample(&sample);
39 ao_ms5607_convert(&sample, &value);
43 #define FILTER_SHIFT 3
44 #define SAMPLE_SLEEP AO_MS_TO_TICKS(96)
46 /* 16 sample, or about two seconds worth */
47 #define GROUND_AVG_SHIFT 4
48 #define GROUND_AVG (1 << GROUND_AVG_SHIFT)
50 /* Pressure change (in Pa) to detect boost */
51 #define BOOST_DETECT 120 /* 10m at sea level, 12m at 2000m */
53 /* Wait after power on before doing anything to give the user time to assemble the rocket */
54 #define BOOST_DELAY AO_SEC_TO_TICKS(30)
56 /* Pressure change (in Pa) to detect landing */
57 #define LAND_DETECT 12 /* 1m at sea level, 1.2m at 2000m */
60 ao_compute_height(void)
62 ground_alt = ao_pa_to_altitude(pa_ground);
63 max_alt = ao_pa_to_altitude(pa_min);
64 ao_max_height = max_alt - ground_alt;
71 ao_eeprom_write(0, &pa_ground, sizeof (pa_ground));
72 ao_eeprom_write(sizeof (pa_ground), &pa_min, sizeof (pa_min));
76 ao_restore_flight(void)
78 ao_eeprom_read(0, &pa_ground, sizeof (pa_ground));
79 ao_eeprom_read(sizeof (pa_ground), &pa_min, sizeof (pa_min));
89 uint8_t dump_eeprom = 0;
91 ao_led_init(LEDS_AVAILABLE);
96 /* Set MOSI and CLK as inputs with pull-ups */
97 DDRB &= ~(1 << 0) | (1 << 2);
98 PORTB |= (1 << 0) | (1 << 2);
100 /* Check to see if either MOSI or CLK are pulled low by the
101 * user shorting them to ground. If so, dump the eeprom out
102 * via the LED. Wait for the shorting wire to go away before
105 while ((PINB & ((1 << 0) | (1 << 2))) != ((1 << 0) | (1 << 2)))
107 PORTB &= ~(1 << 0) | (1 << 2);
113 ao_report_altitude();
122 /* Check to see if there's a flight recorded in memory */
123 if (dump_eeprom && ao_log_micro_scan())
127 ao_delay(BOOST_DELAY);
128 /* Wait for motion, averaging values to get ground pressure */
131 pa_avg = pa_ground = pa << FILTER_SHIFT;
134 time += SAMPLE_SLEEP;
135 if (sample_count == 0)
136 ao_led_on(AO_LED_BLUE);
137 ao_delay_until(time);
139 if (sample_count == 0)
140 ao_led_off(AO_LED_BLUE);
141 pa_avg = pa_avg - (pa_avg >> FILTER_SHIFT) + pa;
142 pa_diff = pa_ground - pa_avg;
144 /* Check for a significant pressure change */
145 if (pa_diff > (BOOST_DETECT << FILTER_SHIFT))
148 if (sample_count < GROUND_AVG * 2) {
149 if (sample_count < GROUND_AVG)
153 pa_ground = pa_sum >> (GROUND_AVG_SHIFT - FILTER_SHIFT);
159 pa_ground >>= FILTER_SHIFT;
162 ao_log_micro_data(AO_LOG_MICRO_GROUND | pa_ground);
165 /* Now sit around until the pressure is stable again and record the max */
169 pa_interval_min = pa_avg;
170 pa_interval_max = pa_avg;
172 time += SAMPLE_SLEEP;
173 ao_delay_until(time);
174 if ((sample_count & 3) == 0)
175 ao_led_on(AO_LED_BLUE);
177 if ((sample_count & 3) == 0)
178 ao_led_off(AO_LED_BLUE);
180 ao_log_micro_data(AO_LOG_MICRO_DATA | pa);
182 pa_avg = pa_avg - (pa_avg >> FILTER_SHIFT) + pa;
186 if (sample_count == (GROUND_AVG - 1)) {
187 pa_diff = pa_interval_max - pa_interval_min;
189 /* Check to see if the pressure is now stable */
190 if (pa_diff < (LAND_DETECT << FILTER_SHIFT))
193 pa_interval_min = pa_avg;
194 pa_interval_max = pa_avg;
196 if (pa_avg < pa_interval_min)
197 pa_interval_min = pa_avg;
198 if (pa_avg > pa_interval_max)
199 pa_interval_max = pa_avg;
203 pa_min >>= FILTER_SHIFT;
205 ao_log_micro_data(AO_LOG_MICRO_DONE | pa_min);
209 ao_report_altitude();
212 set_sleep_mode(SLEEP_MODE_PWR_DOWN);