#ifndef chrono_h #define chrono_h /* chrono.h */ /* io - Input & Output with Artificial Intelligence (ai) support on AVR. {{{ * * Copyright (C) 2008 Dufour Jérémy * * APBTeam: * Web: http://apbteam.org/ * Email: team AT apbteam DOT org * * 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. * * }}} */ /** * @file Module to manage the chrono responsible to stop the bot after 90s. * It uses the timer/counter 1 (16 bits), configured with a prescaler set to * 256. * This way, we need to overflow 79.10071 for a match of 90s: * match_duration / (1 / (AC_FREQ / (Prescaler * (TOP + 1)))) * It will overflow 79 times and them reset the timer/counter to 58982 * (TOP - ((TOP + 1) / 10)). */ #include "modules/utils/utils.h" /* regv */ #include "io.h" /* Registers for timer/counter 1 */ /** * Number of overflow of the timer/counter 1 before doing the last one. */ #define CHRONO_OVERFLOW_MAX 70 /** * Number of TIC to restart from for the last overflow. */ #define CHRONO_RESTART_TIC 58982 /** * Match is finished. * This variable will be set to 0 when the match is over. */ static uint8_t chrono_match_over; /** * Overflow counter. */ static volatile uint8_t chrono_ov_count_; /** * Initialize the chrono timer/counter 1. */ static inline void chrono_init (void) { /* Presaler = 256 */ TCCR1B = regv (ICNC1, ICES1, 5, WGM13, WGM12, CS12, CS11, CS10, 0, 1, 0, 0, 0, 1, 0, 0); /* Enable overflow interrupt */ set_bit (TIMSK, TOIE1); } /* Overflow of timer/counter 1 handler. */ SIGNAL (SIG_OVERFLOW1) { switch (++chrono_ov_count_) { case CHRONO_OVERFLOW_MAX: /* Last but not complete overflow */ TCNT1 = CHRONO_RESTART_TIC; break; case CHRONO_OVERFLOW_MAX + 1: /* End of match! */ chrono_match_over = 1; break; } } #endif /* chrono_h */