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.
21 #define GRAVITY 9.80665
24 #define AO_DATA_ADC (1 << 0)
30 #include <ao_ms5607.h>
31 #define AO_DATA_MS5607 (1 << 1)
33 #define AO_DATA_MS5607 0
37 #include <ao_mpu6000.h>
38 #define AO_DATA_MPU6000 (1 << 2)
40 #define AO_DATA_MPU6000 0
44 #include <ao_hmc5883.h>
45 #define AO_DATA_HMC5883 (1 << 3)
47 #define AO_DATA_HMC5883 0
51 #include <ao_mma655x.h>
52 #define AO_DATA_MMA655X (1 << 4)
54 #define AO_DATA_MMA655X 0
59 #define AO_DATA_ALL (AO_DATA_ADC|AO_DATA_MS5607|AO_DATA_MPU6000|AO_DATA_HMC5883|AO_DATA_MMA655X)
67 struct ao_ms5607_sample ms5607_raw;
68 struct ao_ms5607_value ms5607_cooked;
71 struct ao_mpu6000_sample mpu6000;
77 struct ao_hmc5883_sample hmc5883;
84 #define ao_data_ring_next(n) (((n) + 1) & (AO_DATA_RING - 1))
85 #define ao_data_ring_prev(n) (((n) - 1) & (AO_DATA_RING - 1))
87 /* Get a copy of the last complete sample set */
89 ao_data_get(__xdata struct ao_data *packet);
91 extern volatile __xdata struct ao_data ao_data_ring[AO_DATA_RING];
92 extern volatile __data uint8_t ao_data_head;
93 extern volatile __data uint8_t ao_data_present;
94 extern volatile __data uint8_t ao_data_count;
97 * Mark a section of data as ready, check for data complete
99 #define AO_DATA_PRESENT(bit) (ao_data_present |= (bit))
102 * Wait until it is time to write a sensor sample; this is
103 * signaled by the timer tick
105 #define AO_DATA_WAIT() do { \
106 ao_sleep(DATA_TO_XDATA ((void *) &ao_data_count)); \
109 #endif /* AO_DATA_RING */
111 #if !HAS_BARO && HAS_MS5607
113 /* Either an MS5607 or an MS5611 hooked to a SPI port
118 typedef int32_t pres_t;
121 #define AO_ALT_TYPE int32_t
124 typedef AO_ALT_TYPE alt_t;
126 #define ao_data_pres_cook(packet) ao_ms5607_convert(&packet->ms5607_raw, &packet->ms5607_cooked)
128 #define ao_data_pres(packet) ((packet)->ms5607_cooked.pres)
129 #define ao_data_temp(packet) ((packet)->ms5607_cooked.temp)
131 #define pres_to_altitude(p) ao_pa_to_altitude(p)
135 #if !HAS_BARO && HAS_ADC
139 typedef int16_t pres_t;
140 typedef int16_t alt_t;
142 #define ao_data_pres(packet) ((packet)->adc.pres)
143 #define ao_data_temp(packet) ((packet)->adc.temp)
144 #define pres_to_altitude(p) ao_pres_to_altitude(p)
145 #define ao_data_pres_cook(p)
150 typedef int16_t alt_t;
154 * Need a few macros to pull data from the sensors:
156 * ao_data_accel_sample - pull raw sensor and convert to normalized values
157 * ao_data_accel - pull normalized value (lives in the same memory)
158 * ao_data_set_accel - store normalized value back in the sensor location
159 * ao_data_accel_invert - flip rocket ends for positive acceleration
164 /* This section is for an analog accelerometer hooked to one of the ADC pins. As
165 * those are 5V parts, this also requires that the 5V supply be hooked to to anothe ADC
166 * pin so that the both can be measured to correct for changes between the 3.3V and 5V rails
169 typedef int16_t accel_t;
170 #define ao_data_accel(packet) ((packet)->adc.accel)
171 #define ao_data_set_accel(packet, a) ((packet)->adc.accel = (a))
172 #define ao_data_accel_invert(a) (0x7fff -(a))
175 * Ok, the math here is a bit tricky.
177 * ao_sample_accel: ADC output for acceleration
178 * ao_accel_ref: ADC output for the 5V reference.
179 * ao_cook_accel: Corrected acceleration value
180 * Vcc: 3.3V supply to the CC1111
181 * Vac: 5V supply to the accelerometer
182 * accel: input voltage to accelerometer ADC pin
183 * ref: input voltage to 5V reference ADC pin
186 * Measured acceleration is ratiometric to Vcc:
188 * ao_sample_accel accel
189 * ------------ = -----
192 * Measured 5v reference is also ratiometric to Vcc:
195 * ------------ = -----
199 * ao_accel_ref = 32767 * (ref / Vcc)
201 * Acceleration is measured ratiometric to the 5V supply,
202 * so what we want is:
204 * ao_cook_accel accel
205 * ------------- = -----
213 * ao_sample_accel 32767
214 * = ------------ * ------------
217 * Multiply through by 32767:
219 * ao_sample_accel * 32767
220 * ao_cook_accel = --------------------
223 * Now, the tricky part. Getting this to compile efficiently
224 * and keeping all of the values in-range.
226 * First off, we need to use a shift of 16 instead of * 32767 as SDCC
227 * does the obvious optimizations for byte-granularity shifts:
229 * ao_cook_accel = (ao_sample_accel << 16) / ao_accel_ref
231 * Next, lets check our input ranges:
233 * 0 <= ao_sample_accel <= 0x7fff (singled ended ADC conversion)
234 * 0x7000 <= ao_accel_ref <= 0x7fff (the 5V ref value is close to 0x7fff)
236 * Plugging in our input ranges, we get an output range of 0 - 0x12490,
237 * which is 17 bits. That won't work. If we take the accel ref and shift
238 * by a bit, we'll change its range:
240 * 0xe000 <= ao_accel_ref<<1 <= 0xfffe
242 * ao_cook_accel = (ao_sample_accel << 16) / (ao_accel_ref << 1)
244 * Now the output range is 0 - 0x9248, which nicely fits in 16 bits. It
245 * is, however, one bit too large for our signed computations. So, we
246 * take the result and shift that by a bit:
248 * ao_cook_accel = ((ao_sample_accel << 16) / (ao_accel_ref << 1)) >> 1
250 * This finally creates an output range of 0 - 0x4924. As the ADC only
251 * provides 11 bits of data, we haven't actually lost any precision,
252 * just dropped a bit of noise off the low end.
257 #define ao_data_accel_cook(packet) \
258 ((uint16_t) ((((uint32_t) (packet)->adc.accel << 16) / ((packet)->adc.accel_ref << 1))) >> 1)
262 #define ao_data_accel_cook(packet) ((packet)->adc.accel)
264 #endif /* HAS_ACCEL_REF */
266 #endif /* HAS_ACCEL */
268 #if !HAS_ACCEL && HAS_MMA655X
272 typedef int16_t accel_t;
274 /* MMA655X is hooked up so that positive values represent negative acceleration */
276 #define AO_ACCEL_INVERT 4095
278 #define ao_data_accel(packet) ((packet)->mma655x)
279 #if AO_MMA655X_INVERT
280 #define ao_data_accel_cook(packet) (AO_ACCEL_INVERT - (packet)->mma655x)
282 #define ao_data_accel_cook(packet) ((packet)->mma655x)
284 #define ao_data_set_accel(packet, accel) ((packet)->mma655x = (accel))
285 #define ao_data_accel_invert(accel) (AO_ACCEL_INVERT - (accel))
289 #if !HAS_ACCEL && HAS_MPU6000
293 #define AO_ACCEL_INVERT 0
295 typedef int16_t accel_t;
297 /* MPU6000 is hooked up so that positive y is positive acceleration */
298 #define ao_data_accel(packet) ((packet)->z_accel)
299 #define ao_data_accel_cook(packet) (-(packet)->mpu6000.accel_y)
300 #define ao_data_set_accel(packet, accel) ((packet)->z_accel = (accel))
301 #define ao_data_accel_invert(a) (-(a))
305 #if !HAS_GYRO && HAS_MPU6000
309 typedef int16_t gyro_t; /* in raw sample units */
310 typedef int16_t angle_t; /* in degrees */
312 /* Y axis is aligned with the direction of motion (along) */
313 /* X axis is aligned in the other board axis (across) */
314 /* Z axis is aligned perpendicular to the board (through) */
316 #define ao_data_along(packet) ((packet)->mpu6000.accel_y)
317 #define ao_data_across(packet) ((packet)->mpu6000.accel_x)
318 #define ao_data_through(packet) ((packet)->mpu6000.accel_z)
320 #define ao_data_roll(packet) ((packet)->mpu6000.gyro_y)
321 #define ao_data_pitch(packet) ((packet)->mpu6000.gyro_x)
322 #define ao_data_yaw(packet) ((packet)->mpu6000.gyro_z)
326 #if !HAS_MAG && HAS_HMC5883
330 typedef int16_t ao_mag_t; /* in raw sample units */
332 #define ao_data_mag_along(packet) ((packet)->hmc5883.x)
333 #define ao_data_mag_across(packet) ((packet)->hmc5883.y)
334 #define ao_data_mag_through(packet) ((packet)->hmc5883.z)
338 #endif /* _AO_DATA_H_ */