timer_common_f0234.c

Go to the documentation of this file.

/** @addtogroup timer_file
 
*/
 
/*
 * This file is part of the libopencm3 project.
 *
 * Copyright (C) 2010 Edward Cheeseman <evbuilder@users.sourceforge.org>
 * Copyright (C) 2011 Stephen Caudle <scaudle@doceme.com>
 *
 * This library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library.  If not, see <http://www.gnu.org/licenses/>.
 */
 
/**@{*/
 
#include <libopencm3/stm32/timer.h>
 
/*---------------------------------------------------------------------------*/
/** @brief Set Input Polarity
 
The timer channel must be set to input capture mode.
 
@param[in] timer_peripheral Unsigned int32. Timer register address base
@param[in] ic ::tim_ic_id. Input Capture channel designator.
@param[in] pol ::tim_ic_pol. Input Capture polarity control.
*/
 
void timer_ic_set_polarity(uint32_t timer_peripheral, enum tim_ic_id ic,
                           enum tim_ic_pol pol)
{
        /* Clear CCxP and CCxNP to zero. For both edge trigger both fields are
         * set. Case 10 is invalid.
         */
        TIM_CCER(timer_peripheral) &= ~(0xa << (ic * 4));
        switch (pol) {
        case TIM_IC_RISING:  /* 00 */
                break;
        case TIM_IC_BOTH:    /* 11 */
                TIM_CCER(timer_peripheral) |= (0xa << (ic * 4));
                break;
        case TIM_IC_FALLING: /* 01 */
                TIM_CCER(timer_peripheral) |= (0x2 << (ic * 4));
        }
}
/**@}*/