diff options
Diffstat (limited to 'ao_adc.c')
| -rw-r--r-- | ao_adc.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/ao_adc.c b/ao_adc.c new file mode 100644 index 00000000..d45e10b1 --- /dev/null +++ b/ao_adc.c @@ -0,0 +1,73 @@ +/* + * Copyright © 2009 Keith Packard <keithp@keithp.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include "ao.h" + +__xdata struct ao_adc ao_adc_ring[ADC_RING]; +__data uint8_t ao_adc_head; + +void ao_adc_isr(void) interrupt 1 +{ + uint8_t sequence; + uint8_t __xdata *a; + + sequence = (ADCCON2 & ADCCON2_SCH_MASK) >> ADCCON2_SCH_SHIFT; + a = (uint8_t __xdata *) (&ao_adc_ring[ao_adc_head].accel + sequence); + a[0] = ADCL; + a[1] = ADCH; + if (sequence < 5) { + /* start next channel conversion */ + ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | (sequence + 1); + } else { + /* record this conversion series */ + ao_adc_ring[ao_adc_head].tick = ao_time; + ao_adc_head++; + if (ao_adc_head == ADC_RING) + ao_adc_head = 0; + ao_wakeup(ao_adc_ring); + } +} + +void ao_adc_init(void) +{ + ADCCFG = ((1 << 0) | /* acceleration */ + (1 << 1) | /* pressure */ + (1 << 2) | /* temperature */ + (1 << 3) | /* battery voltage */ + (1 << 4) | /* drogue sense */ + (1 << 5)); /* main sense */ + + /* enable interrupts */ + ADCIF = 0; + IEN0 |= IEN0_ADCIE; +} + +void ao_adc_poll(void) +{ + ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | 0; +} + +void ao_adc_get(__xdata struct ao_adc *packet) +{ + uint8_t i = ao_adc_head; + if (i == 0) + i = ADC_RING; + i--; + memcpy(packet, &ao_adc_ring[i], sizeof (struct ao_adc)); +} + |