From c04b8fe1c42dd36b384bdc3379734d6c8bfe7996 Mon Sep 17 00:00:00 2001 From: Jérémy Dufour Date: Sat, 14 Mar 2009 23:24:05 +0100 Subject: * digital/io/src: - clean main timer module. --- digital/io/src/main_timer.avr.c | 58 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 digital/io/src/main_timer.avr.c (limited to 'digital/io/src/main_timer.avr.c') diff --git a/digital/io/src/main_timer.avr.c b/digital/io/src/main_timer.avr.c new file mode 100644 index 00000000..8f343403 --- /dev/null +++ b/digital/io/src/main_timer.avr.c @@ -0,0 +1,58 @@ +/* main_timer.avr.c */ +/* io - Input & Output with Artificial Intelligence (ai) support on AVR. {{{ + * + * Copyright (C) 2009 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. + * + * }}} */ + +#include "common.h" + +#include "main_timer.h" + +#include "modules/utils/utils.h" +#include "io.h" + +void +main_timer_init (void) +{ + /* Fov = F_io / (prescaler * (TOP + 1)) + * TOP = 0xff + * prescaler = 256 + * Tov = 1 / Fov = 4.444 ms */ + /* Note: if you change this, update MT_TC0_*. */ + TCCR0 = regv (FOC0, WGM00, COM01, COM0, WGM01, CS02, CS01, CS00, + 0, 0, 0, 0, 0, 1, 1, 0); +} + +uint8_t +main_timer_wait (void) +{ + /* We have reached overflow. */ + uint8_t count_before_ov = 1; + /* Loop until an overflow of the timer occurs. */ + while (!(TIFR & _BV (TOV0))) + /* We have not reached overflow. */ + count_before_ov = 0; + /* Write 1 to clear overflow. */ + TIFR = _BV (TOV0); + + return count_before_ov; +} -- cgit v1.2.3