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;
120 #define AO_ALT_TYPE int32_t
122 typedef AO_ALT_TYPE alt_t;
124 #define ao_data_pres_cook(packet) ao_ms5607_convert(&packet->ms5607_raw, &packet->ms5607_cooked)
126 #define ao_data_pres(packet) ((packet)->ms5607_cooked.pres)
127 #define ao_data_temp(packet) ((packet)->ms5607_cooked.temp)
129 #define pres_to_altitude(p) ao_pa_to_altitude(p)
133 #if !HAS_BARO && HAS_ADC
137 typedef int16_t pres_t;
138 typedef int16_t alt_t;
140 #define ao_data_pres(packet) ((packet)->adc.pres)
141 #define ao_data_temp(packet) ((packet)->adc.temp)
142 #define pres_to_altitude(p) ao_pres_to_altitude(p)
143 #define ao_data_pres_cook(p)
148 * Need a few macros to pull data from the sensors:
150 * ao_data_accel_sample - pull raw sensor and convert to normalized values
151 * ao_data_accel - pull normalized value (lives in the same memory)
152 * ao_data_set_accel - store normalized value back in the sensor location
153 * ao_data_accel_invert - flip rocket ends for positive acceleration
158 /* This section is for an analog accelerometer hooked to one of the ADC pins. As
159 * those are 5V parts, this also requires that the 5V supply be hooked to to anothe ADC
160 * pin so that the both can be measured to correct for changes between the 3.3V and 5V rails
163 typedef int16_t accel_t;
164 #define ao_data_accel(packet) ((packet)->adc.accel)
165 #define ao_data_set_accel(packet, a) ((packet)->adc.accel = (a))
166 #define ao_data_accel_invert(a) (0x7fff -(a))
169 * Ok, the math here is a bit tricky.
171 * ao_sample_accel: ADC output for acceleration
172 * ao_accel_ref: ADC output for the 5V reference.
173 * ao_cook_accel: Corrected acceleration value
174 * Vcc: 3.3V supply to the CC1111
175 * Vac: 5V supply to the accelerometer
176 * accel: input voltage to accelerometer ADC pin
177 * ref: input voltage to 5V reference ADC pin
180 * Measured acceleration is ratiometric to Vcc:
182 * ao_sample_accel accel
183 * ------------ = -----
186 * Measured 5v reference is also ratiometric to Vcc:
189 * ------------ = -----
193 * ao_accel_ref = 32767 * (ref / Vcc)
195 * Acceleration is measured ratiometric to the 5V supply,
196 * so what we want is:
198 * ao_cook_accel accel
199 * ------------- = -----
207 * ao_sample_accel 32767
208 * = ------------ * ------------
211 * Multiply through by 32767:
213 * ao_sample_accel * 32767
214 * ao_cook_accel = --------------------
217 * Now, the tricky part. Getting this to compile efficiently
218 * and keeping all of the values in-range.
220 * First off, we need to use a shift of 16 instead of * 32767 as SDCC
221 * does the obvious optimizations for byte-granularity shifts:
223 * ao_cook_accel = (ao_sample_accel << 16) / ao_accel_ref
225 * Next, lets check our input ranges:
227 * 0 <= ao_sample_accel <= 0x7fff (singled ended ADC conversion)
228 * 0x7000 <= ao_accel_ref <= 0x7fff (the 5V ref value is close to 0x7fff)
230 * Plugging in our input ranges, we get an output range of 0 - 0x12490,
231 * which is 17 bits. That won't work. If we take the accel ref and shift
232 * by a bit, we'll change its range:
234 * 0xe000 <= ao_accel_ref<<1 <= 0xfffe
236 * ao_cook_accel = (ao_sample_accel << 16) / (ao_accel_ref << 1)
238 * Now the output range is 0 - 0x9248, which nicely fits in 16 bits. It
239 * is, however, one bit too large for our signed computations. So, we
240 * take the result and shift that by a bit:
242 * ao_cook_accel = ((ao_sample_accel << 16) / (ao_accel_ref << 1)) >> 1
244 * This finally creates an output range of 0 - 0x4924. As the ADC only
245 * provides 11 bits of data, we haven't actually lost any precision,
246 * just dropped a bit of noise off the low end.
251 #define ao_data_accel_cook(packet) \
252 ((uint16_t) ((((uint32_t) (packet)->adc.accel << 16) / ((packet)->adc.accel_ref << 1))) >> 1)
256 #define ao_data_accel_cook(packet) ((packet)->adc.accel)
258 #endif /* HAS_ACCEL_REF */
260 #endif /* HAS_ACCEL */
262 #if !HAS_ACCEL && HAS_MMA655X
266 typedef int16_t accel_t;
268 /* MMA655X is hooked up so that positive values represent negative acceleration */
270 #define AO_ACCEL_INVERT 4095
272 #define ao_data_accel(packet) ((packet)->mma655x)
273 #if AO_MMA655X_INVERT
274 #define ao_data_accel_cook(packet) (AO_ACCEL_INVERT - (packet)->mma655x)
276 #define ao_data_accel_cook(packet) ((packet)->mma655x)
278 #define ao_data_set_accel(packet, accel) ((packet)->mma655x = (accel))
279 #define ao_data_accel_invert(accel) (AO_ACCEL_INVERT - (accel))
283 #if !HAS_ACCEL && HAS_MPU6000
287 #define AO_ACCEL_INVERT 0
289 typedef int16_t accel_t;
291 /* MPU6000 is hooked up so that positive y is positive acceleration */
292 #define ao_data_accel(packet) ((packet)->z_accel)
293 #define ao_data_accel_cook(packet) (-(packet)->mpu6000.accel_y)
294 #define ao_data_set_accel(packet, accel) ((packet)->z_accel = (accel))
295 #define ao_data_accel_invert(a) (-(a))
299 #if !HAS_GYRO && HAS_MPU6000
303 typedef int16_t gyro_t; /* in raw sample units */
304 typedef int16_t angle_t; /* in degrees */
306 /* Y axis is aligned with the direction of motion (along) */
307 /* X axis is aligned in the other board axis (across) */
308 /* Z axis is aligned perpendicular to the board (through) */
310 #define ao_data_along(packet) ((packet)->mpu6000.accel_y)
311 #define ao_data_across(packet) ((packet)->mpu6000.accel_x)
312 #define ao_data_through(packet) ((packet)->mpu6000.accel_z)
314 #define ao_data_roll(packet) ((packet)->mpu6000.gyro_y)
315 #define ao_data_pitch(packet) ((packet)->mpu6000.gyro_x)
316 #define ao_data_yaw(packet) ((packet)->mpu6000.gyro_z)
320 #if !HAS_MAG && HAS_HMC5883
324 typedef int16_t ao_mag_t; /* in raw sample units */
326 #define ao_data_mag_along(packet) ((packet)->hmc5883.x)
327 #define ao_data_mag_across(packet) ((packet)->hmc5883.y)
328 #define ao_data_mag_through(packet) ((packet)->hmc5883.z)
332 #endif /* _AO_DATA_H_ */