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Diffstat (limited to 'src/avr/ao_pwmin.c')
| -rw-r--r-- | src/avr/ao_pwmin.c | 90 |
1 files changed, 0 insertions, 90 deletions
diff --git a/src/avr/ao_pwmin.c b/src/avr/ao_pwmin.c deleted file mode 100644 index 84397357..00000000 --- a/src/avr/ao_pwmin.c +++ /dev/null @@ -1,90 +0,0 @@ -/* - * Copyright © 2012 Robert D. Garbee <robert@gag.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; version 2 of the License. - * - * 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" -#include "ao_pwmin.h" - -/* - * This code implements a PWM input using ICP3. - * - * The initial use is to measure wind speed in the ULA/Ball summer intern - * project payload developed at Challenger Middle School. - */ - -volatile __data uint16_t ao_icp3_count = 0; -volatile __data uint16_t ao_icp3_last = 0; - -uint16_t ao_icp3(void) -{ - uint16_t v; - ao_arch_critical( - v = ao_icp3_count; - ); - return v; -} - -static void -ao_pwmin_display(void) __reentrant -{ - /* display the most recent value */ - printf("icp 3: %5u\n", ao_icp3()); - -} - - -ISR(TIMER3_CAPT_vect) -{ - - uint8_t lo = ICR3L; - uint8_t hi = ICR3H; - uint16_t ao_icp3_this = (hi <<8) | lo; - - /* handling counter rollovers */ - if (ao_icp3_this >= ao_icp3_last) - ao_icp3_count = ao_icp3_this - ao_icp3_last; - else - ao_icp3_count = ao_icp3_this + (65536 - ao_icp3_last); - ao_icp3_last = ao_icp3_this; -} - -__code struct ao_cmds ao_pwmin_cmds[] = { - { ao_pwmin_display, "p\0PWM input" }, - { 0, NULL }, -}; - -void -ao_pwmin_init(void) -{ - /* do hardware setup here */ - TCCR3A = ((0 << WGM31) | /* normal mode, OCR3A */ - (0 << WGM30)); /* normal mode, OCR3A */ - TCCR3B = ((1 << ICNC3) | /* input capture noise canceler on */ - (0 << ICES3) | /* input capture on falling edge (don't care) */ - (0 << WGM33) | /* normal mode, OCR3A */ - (0 << WGM32) | /* normal mode, OCR3A */ - (3 << CS30)); /* clk/64 from prescaler */ - - - - TIMSK3 = (1 << ICIE3); /* Interrupt on input compare */ - - /* set the spike filter bit in the TCCR3B register */ - - ao_cmd_register(&ao_pwmin_cmds[0]); -} - - |