diff options
| -rw-r--r-- | doc/altos.xsl | 11 | ||||
| -rw-r--r-- | src/ao.h | 10 | ||||
| -rw-r--r-- | src/ao_adc.c | 38 | ||||
| -rw-r--r-- | src/ao_config.c | 6 | ||||
| -rw-r--r-- | src/ao_flight.c | 95 | ||||
| -rw-r--r-- | src/ao_flight_test.c | 4 | ||||
| -rw-r--r-- | src/ao_ignite.c | 1 | ||||
| -rw-r--r-- | src/ao_log.c | 4 | ||||
| -rw-r--r-- | src/ao_pins.h | 3 | ||||
| -rw-r--r-- | src/ao_test.c | 2 |
10 files changed, 136 insertions, 38 deletions
diff --git a/doc/altos.xsl b/doc/altos.xsl index 295864fe..37bb58da 100644 --- a/doc/altos.xsl +++ b/doc/altos.xsl @@ -386,17 +386,6 @@ </para> </section> <section> - <title>ao_wake_task</title> - <programlisting> - void - ao_wake_task(__xdata struct ao_task *task) - </programlisting> - <para> - Force a specific task to wake up, independent of which - 'wchan' it is waiting for. - </para> - </section> - <section> <title>ao_start_scheduler</title> <programlisting> void @@ -163,6 +163,11 @@ struct ao_adc { #endif #if HAS_ADC + +#ifndef HAS_ACCEL_REF +#error Please define HAS_ACCEL_REF +#endif + /* * ao_adc.c */ @@ -178,6 +183,9 @@ struct ao_adc { */ extern volatile __xdata struct ao_adc ao_adc_ring[AO_ADC_RING]; extern volatile __data uint8_t ao_adc_head; +#if HAS_ACCEL_REF +extern volatile __xdata uint16_t ao_accel_ref[AO_ADC_RING]; +#endif /* Trigger a conversion sequence (called from the timer interrupt) */ void @@ -649,7 +657,7 @@ enum ao_flight_state { ao_flight_invalid = 9 }; -extern __xdata struct ao_adc ao_flight_data; +extern __data uint8_t ao_flight_adc; extern __pdata enum ao_flight_state ao_flight_state; extern __pdata uint16_t ao_flight_tick; extern __pdata int16_t ao_flight_accel; diff --git a/src/ao_adc.c b/src/ao_adc.c index 49d2519e..3adf9b2e 100644 --- a/src/ao_adc.c +++ b/src/ao_adc.c @@ -19,24 +19,25 @@ #include "ao_pins.h" volatile __xdata struct ao_adc ao_adc_ring[AO_ADC_RING]; +#if HAS_ACCEL_REF +volatile __xdata uint16_t ao_accel_ref[AO_ADC_RING]; +#endif volatile __data uint8_t ao_adc_head; void ao_adc_poll(void) { +#if HAS_ACCEL_REF + ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | 2; +#else ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | 0; -} - -void -ao_adc_sleep(void) -{ - ao_sleep(&ao_adc_ring); +#endif } void ao_adc_get(__xdata struct ao_adc *packet) { - uint8_t i = ao_adc_ring_prev(ao_adc_head); + uint8_t i = ao_adc_ring_prev(ao_flight_adc); memcpy(packet, &ao_adc_ring[i], sizeof (struct ao_adc)); } @@ -47,25 +48,34 @@ ao_adc_isr(void) __interrupt 1 uint8_t __xdata *a; sequence = (ADCCON2 & ADCCON2_SCH_MASK) >> ADCCON2_SCH_SHIFT; - if (sequence == ADCCON3_ECH_TEMP) - sequence = 2; - a = (uint8_t __xdata *) (&ao_adc_ring[ao_adc_head].accel + sequence); +#if HAS_ACCEL_REF + if (sequence == 2) { + a = (uint8_t __xdata *) (&ao_accel_ref[ao_adc_head]); + sequence = 0; + } else +#endif + { + if (sequence == ADCCON3_ECH_TEMP) + sequence = 2; + a = (uint8_t __xdata *) (&ao_adc_ring[ao_adc_head].accel + sequence); + sequence++; + } a[0] = ADCL; a[1] = ADCH; - if (sequence < 5) { + if (sequence < 6) { #if HAS_EXTERNAL_TEMP == 0 /* start next channel conversion */ /* v0.2 replaces external temp sensor with internal one */ - if (sequence == 1) + if (sequence == 2) ADCCON3 = ADCCON3_EREF_1_25 | ADCCON3_EDIV_512 | ADCCON3_ECH_TEMP; else #endif - ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | (sequence + 1); + ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | sequence; } else { /* record this conversion series */ ao_adc_ring[ao_adc_head].tick = ao_time(); ao_adc_head = ao_adc_ring_next(ao_adc_head); - ao_wakeup(ao_adc_ring); + ao_wakeup(DATA_TO_XDATA(&ao_adc_head)); } } diff --git a/src/ao_config.c b/src/ao_config.c index e97b7eb1..bbee3b44 100644 --- a/src/ao_config.c +++ b/src/ao_config.c @@ -209,10 +209,10 @@ ao_config_accel_calibrate_auto(char *orientation) __reentrant puts("Calibrating..."); flush(); i = ACCEL_CALIBRATE_SAMPLES; accel_total = 0; - cal_adc_ring = ao_adc_head; + cal_adc_ring = ao_flight_adc; while (i) { - ao_sleep(&ao_adc_ring); - while (i && cal_adc_ring != ao_adc_head) { + ao_sleep(DATA_TO_XDATA(&ao_flight_adc)); + while (i && cal_adc_ring != ao_flight_adc) { accel_total += (int32_t) ao_adc_ring[cal_adc_ring].accel; cal_adc_ring = ao_adc_ring_next(cal_adc_ring); i--; diff --git a/src/ao_flight.c b/src/ao_flight.c index e99692a3..81aecad3 100644 --- a/src/ao_flight.c +++ b/src/ao_flight.c @@ -146,16 +146,103 @@ ao_flight(void) ao_raw_pres = 0; ao_flight_tick = 0; for (;;) { - ao_sleep(&ao_adc_ring); + ao_wakeup(DATA_TO_XDATA(&ao_flight_adc)); + ao_sleep(DATA_TO_XDATA(&ao_adc_head)); while (ao_flight_adc != ao_adc_head) { __pdata uint8_t ticks; __pdata int16_t ao_vel_change; + __xdata struct ao_adc *ao_adc; ao_flight_prev_tick = ao_flight_tick; /* Capture a sample */ - ao_raw_accel = ao_adc_ring[ao_flight_adc].accel; - ao_raw_pres = ao_adc_ring[ao_flight_adc].pres; - ao_flight_tick = ao_adc_ring[ao_flight_adc].tick; + ao_adc = &ao_adc_ring[ao_flight_adc]; + ao_flight_tick = ao_adc->tick; + ao_raw_accel = ao_adc->accel; +#if HAS_ACCEL_REF + /* + * Ok, the math here is a bit tricky. + * + * ao_raw_accel: ADC output for acceleration + * ao_accel_ref: ADC output for the 5V reference. + * ao_cook_accel: Corrected acceleration value + * Vcc: 3.3V supply to the CC1111 + * Vac: 5V supply to the accelerometer + * accel: input voltage to accelerometer ADC pin + * ref: input voltage to 5V reference ADC pin + * + * + * Measured acceleration is ratiometric to Vcc: + * + * ao_raw_accel accel + * ------------ = ----- + * 32767 Vcc + * + * Measured 5v reference is also ratiometric to Vcc: + * + * ao_accel_ref ref + * ------------ = ----- + * 32767 Vcc + * + * + * ao_accel_ref = 32767 * (ref / Vcc) + * + * Acceleration is measured ratiometric to the 5V supply, + * so what we want is: + * + * ao_cook_accel accel + * ------------- = ----- + * 32767 ref + * + * + * accel Vcc + * = ----- * --- + * Vcc ref + * + * ao_raw_accel 32767 + * = ------------ * ------------ + * 32737 ao_accel_ref + * + * Multiply through by 32767: + * + * ao_raw_accel * 32767 + * ao_cook_accel = -------------------- + * ao_accel_ref + * + * Now, the tricky part. Getting this to compile efficiently + * and keeping all of the values in-range. + * + * First off, we need to use a shift of 16 instead of * 32767 as SDCC + * does the obvious optimizations for byte-granularity shifts: + * + * ao_cook_accel = (ao_raw_accel << 16) / ao_accel_ref + * + * Next, lets check our input ranges: + * + * 0 <= ao_raw_accel <= 0x7fff (singled ended ADC conversion) + * 0x7000 <= ao_accel_ref <= 0x7fff (the 5V ref value is close to 0x7fff) + * + * Plugging in our input ranges, we get an output range of 0 - 0x12490, + * which is 17 bits. That won't work. If we take the accel ref and shift + * by a bit, we'll change its range: + * + * 0xe000 <= ao_accel_ref<<1 <= 0xfffe + * + * ao_cook_accel = (ao_raw_accel << 16) / (ao_accel_ref << 1) + * + * Now the output range is 0 - 0x9248, which nicely fits in 16 bits. It + * is, however, one bit too large for our signed computations. So, we + * take the result and shift that by a bit: + * + * ao_cook_accel = ((ao_raw_accel << 16) / (ao_accel_ref << 1)) >> 1 + * + * This finally creates an output range of 0 - 0x4924. As the ADC only + * provides 11 bits of data, we haven't actually lost any precision, + * just dropped a bit of noise off the low end. + */ + ao_raw_accel = (uint16_t) ((((uint32_t) ao_raw_accel << 16) / (ao_accel_ref[ao_flight_adc] << 1))) >> 1; + ao_adc->accel = ao_raw_accel; +#endif + ao_raw_pres = ao_adc->pres; ao_flight_accel -= ao_flight_accel >> 4; ao_flight_accel += ao_raw_accel >> 4; diff --git a/src/ao_flight_test.c b/src/ao_flight_test.c index e0cfa47a..5c619518 100644 --- a/src/ao_flight_test.c +++ b/src/ao_flight_test.c @@ -180,7 +180,7 @@ void ao_sleep(void *wchan) { ao_dump_state(); - if (wchan == &ao_adc_ring) { + if (wchan == &ao_adc_head) { char type; uint16_t tick; uint16_t a, b; @@ -238,6 +238,8 @@ ao_sleep(void *wchan) switch (type) { case 'F': ao_flight_ground_accel = a; + ao_config.accel_plus_g = a; + ao_config.accel_minus_g = a + 530; ao_flight_started = 1; break; case 'S': diff --git a/src/ao_ignite.c b/src/ao_ignite.c index f2b15dd2..603fcd25 100644 --- a/src/ao_ignite.c +++ b/src/ao_ignite.c @@ -52,7 +52,6 @@ ao_igniter_status(enum ao_igniter igniter) __xdata uint8_t request, firing, fired; __critical { - ao_adc_sleep(); ao_adc_get(&adc); request = ao_ignition[igniter].request; fired = ao_ignition[igniter].fired; diff --git a/src/ao_log.c b/src/ao_log.c index fa072550..099c5f6f 100644 --- a/src/ao_log.c +++ b/src/ao_log.c @@ -99,10 +99,10 @@ ao_log(void) /* Write the whole contents of the ring to the log * when starting up. */ - ao_log_adc_pos = ao_adc_ring_next(ao_adc_head); + ao_log_adc_pos = ao_adc_ring_next(ao_flight_adc); for (;;) { /* Write samples to EEPROM */ - while (ao_log_adc_pos != ao_adc_head) { + while (ao_log_adc_pos != ao_flight_adc) { log.type = AO_LOG_SENSOR; log.tick = ao_adc_ring[ao_log_adc_pos].tick; log.u.sensor.accel = ao_adc_ring[ao_log_adc_pos].accel; diff --git a/src/ao_pins.h b/src/ao_pins.h index 9446964e..2c5b9db5 100644 --- a/src/ao_pins.h +++ b/src/ao_pins.h @@ -31,6 +31,7 @@ #define AO_LED_RED 1 #define LEDS_AVAILABLE (AO_LED_RED) #define HAS_EXTERNAL_TEMP 0 + #define HAS_ACCEL_REF 0 #endif #if defined(TELEMETRUM_V_1_1) @@ -46,6 +47,7 @@ #define AO_LED_RED 1 #define LEDS_AVAILABLE (AO_LED_RED) #define HAS_EXTERNAL_TEMP 0 + #define HAS_ACCEL_REF 1 #define SPI_CS_ON_P1 1 #define SPI_CS_ON_P0 0 #define M25_CS_MASK 0x02 /* CS0 is P1_1 */ @@ -81,6 +83,7 @@ #define AO_LED_GREEN 1 #define LEDS_AVAILABLE (AO_LED_RED|AO_LED_GREEN) #define HAS_EXTERNAL_TEMP 1 + #define HAS_ACCEL_REF 0 #define SPI_CS_ON_P1 1 #define SPI_CS_ON_P0 0 #endif diff --git a/src/ao_test.c b/src/ao_test.c index b9f7d338..14c2eb75 100644 --- a/src/ao_test.c +++ b/src/ao_test.c @@ -53,7 +53,7 @@ blink_1(void) static __xdata struct ao_adc adc; for (;;) { - ao_sleep(&ao_adc_ring); + ao_sleep(&ao_adc_head); ao_adc_get(&adc); if (adc.accel < 15900) ao_led_on(AO_LED_RED); |