/* timer.avr.c */ /* asserv - Position & speed motor control on AVR. {{{ * * Copyright (C) 2005 Nicolas Schodet * * Robot APB Team/Efrei 2006. * Web: http://assos.efrei.fr/robot/ * Email: robot AT efrei DOT fr * * 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. * * }}} */ /* +AutoDec */ /** Initialise the timer. */ static inline void timer_init (void); /** Wait for timer overflow. */ static inline void timer_wait (void); /** Read timer value. Used for performance analysis. */ static inline uint8_t timer_read (void); /* -AutoDec */ /** Initialise the timer. */ static inline void timer_init (void) { TCCR0 = regv (FOC0, WGM00, COM01, COM0, WGM01, CS02, CS01, CS00, 0, 0, 0, 0, 0, 1, 1, 0); /* Fov = F_io / (prescaler * (TOP + 1)) * TOP = 0xff * prescaler = 256 * Tov = 1 / Fov = 4.444 ms */ } /** Wait for timer overflow. */ static inline void timer_wait (void) { while (!(TIFR & _BV (TOV0))) ; /* Write 1 to clear. */ TIFR = _BV (TOV0); } /** Read timer value. Used for performance analysis. */ static inline uint8_t timer_read (void) { return TCNT0; }