/* * Copyright (c) 2008 Swedish Institute of Computer Science * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * Neither the name of the copyright holders nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /** * \file * * \brief * This file will configure the timer during LCD operation. * * \author * Mike Vidales mavida404@gmail.com * */ #include "lcd.h" #include "timer.h" /** * \addtogroup lcd * \{ */ bool timer_flag; /*---------------------------------------------------------------------------*/ /** * \brief TIMER1 init for timer used by LCD. * * The FPU of 8MHz with a prescaler of 1024 equals 7812.5 timer ticks creating a * resolution of 128us per tick. * * NOTE: The TIMER1 interrupt is not enabled in this routine */ void timer_init(void) { /* * Set TIMER1 output compare mode to clear on compare match for OC1A. Also * set the pre-scaler to 1024. */ TCCR1B = (1 << WGM12)|(1 << CS12)|(1 << CS10); /* Set TIMER1 output compare register approx. 1 sec resolution. */ OCR1A = _1_SEC; } /*---------------------------------------------------------------------------*/ /** * \brief Start the timer. */ void timer_start(void) { /* Clear TIMER1 timer counter value. */ TCNT1 = 0; /* Enable TIMER1 output compare interrupt. */ TIMSK1 = (1 << OCIE1A); } /*---------------------------------------------------------------------------*/ /** * \brief Stop the timer. */ void timer_stop(void) { /* Disable TIMER1 output compare interrupt. */ TIMSK1 &= ~(1 << OCIE1A); } /*---------------------------------------------------------------------------*/ /** * \brief This is the interrupt subroutine for the TIMER1 output match comparison. */ ISR (TIMER1_COMPA_vect) { /* Set the irq flag. */ timer_flag = true; } /** \} */