182 lines
8.1 KiB
C
182 lines
8.1 KiB
C
/*
|
|
* Copyright (c) 2015, Zolertia - http://www.zolertia.com
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
*
|
|
* 3. Neither the name of the copyright holder nor the names of its
|
|
* 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 HOLDER 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.
|
|
*/
|
|
/*---------------------------------------------------------------------------*/
|
|
/**
|
|
* \addtogroup cc2538
|
|
* @{
|
|
*
|
|
* \defgroup cc2538-pwm-driver CC2538 PWM driver
|
|
*
|
|
* Driver for the CC2538 PWM on GPTIMER
|
|
*
|
|
* The driver uses the timers A and B of the general purpose timers to create
|
|
* a PWM signal, allowing to set a duty cycle value from 1-100%. This
|
|
* implementation relies on having a peripheral clock of 16MHz, but it can be
|
|
* easily changed (see PWM_FREQ_MIN and PWM_FREQ_MAX values). The reason it is
|
|
* fixed to these frequencies is to have a consistent duty cycle
|
|
* implementation.
|
|
*
|
|
* Depending on the specific needs these limits can be changed to meet a given
|
|
* duty cycle and lower frequencies by using the prescaler (GPTIMER_TnPR).
|
|
*
|
|
* Running a PWM timer prevents the LPM driver from dropping to PM1+.
|
|
*
|
|
* @{
|
|
*
|
|
* \file
|
|
* Header file for the CC2538 PWM driver
|
|
*
|
|
* \author
|
|
* Javier Sanchez <jsanchez@zolertia.com>
|
|
* Antonio Lignan <alinan@zolertia.com>
|
|
*/
|
|
/*---------------------------------------------------------------------------*/
|
|
#ifndef PWM_H_
|
|
#define PWM_H_
|
|
/*---------------------------------------------------------------------------*/
|
|
#include "contiki.h"
|
|
#include "dev/ioc.h"
|
|
#include "dev/gpio.h"
|
|
#include "dev/sys-ctrl.h"
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \name PWM return values
|
|
* @{
|
|
*/
|
|
#define PWM_SUCCESS 0
|
|
#define PWM_ERROR (-1)
|
|
/** @} */
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \name PWM recommended values respect to peripheral clock frequency
|
|
* @{
|
|
*/
|
|
/* Roughly 244 Hz with a 16-MHz system clock, no prescaler */
|
|
#define PWM_SYS_16MHZ_NO_PRES_MIN 0xFFFF
|
|
#define PWM_SYS_16MHZ_NO_PRES_MIN_FREQ 244
|
|
/* Roughly 1 Hz with a 16-MHz system clock, to keep frequency parameter in Hz */
|
|
#define PWM_SYS_16MHZ_PRES_MIN 0x00F42400
|
|
#define PWM_SYS_16MHZ_PRES_MIN_FREQ 1
|
|
/* Yields 160 KHz at 16 MHz and allows down to 1% (integer) duty cycles */
|
|
#define PWM_SYS_16MHZ_NO_PRES_MAX 100
|
|
#define PWM_SYS_16MHZ_NO_PRES_MAX_FREQ 160000
|
|
/** @} */
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \name PWM driver definitions and configuration values
|
|
* @{
|
|
*/
|
|
#define PWM_TIMER_A 0
|
|
#define PWM_TIMER_B 1
|
|
#define PWM_TIMER_0 0
|
|
#define PWM_TIMER_1 1
|
|
#define PWM_TIMER_2 2
|
|
#define PWM_TIMER_3 3
|
|
#define PWM_TIMER_MIN PWM_TIMER_0
|
|
#define PWM_TIMER_MAX PWM_TIMER_3
|
|
#define PWM_SIGNAL_STRAIGHT 1
|
|
#define PWM_SIGNAL_INVERTED 0
|
|
#define PWM_OFF_WHEN_STOP 0
|
|
#define PWM_ON_WHEN_STOP 1
|
|
#define PWM_GPTIMER_CFG_SPLIT_MODE 0x04
|
|
#define PWM_DUTY_MAX 100
|
|
#define PWM_DUTY_MIN 0
|
|
#define PWM_FREQ_MIN PWM_SYS_16MHZ_PRES_MIN_FREQ
|
|
#define PWM_FREQ_MAX PWM_SYS_16MHZ_NO_PRES_MAX_FREQ
|
|
/** @} */
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \name PWM functions
|
|
* @{
|
|
*/
|
|
/** \brief Configures the general purpose timer in PWM mode
|
|
* \param freq PWM frequency (in Hz)
|
|
* \param duty PWM duty cycle (percentage in integers)
|
|
* \param count PWM duty cycle (count number)
|
|
* \param timer General purpose timer to use [0-3]
|
|
* \param ab Select which timer to use (Timer A or B)
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*/
|
|
int8_t pwm_enable(uint32_t freq, uint8_t duty, uint32_t count, uint8_t timer,
|
|
uint8_t ab);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \brief Disables a previously PWM configured GPTn
|
|
* \param timer General purpose timer to disable [0-3]
|
|
* \param ab Select which timer to disable (Timer A or B)
|
|
* \param port Port number used as PWM to disable (set as input GPIO)
|
|
* \param pin Pin number used as PWM to disable (set as input GPIO)
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*
|
|
* This function disables a specific timer (A or B) and reset related registers
|
|
* to default values. The user must explicitely pass the port/pin number of
|
|
* the pin to disable as PWM and to be configured as input GPIO.
|
|
* The module clock is not disabled with this function
|
|
*/
|
|
int8_t pwm_disable(uint8_t timer, uint8_t ab, uint8_t port, uint8_t pin);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \brief Once configured, starts the PWM
|
|
* \param timer General purpose timer to start [0-3]
|
|
* \param ab Select which timer to start (Timer A or B)
|
|
* \param port Port number to use as PWM
|
|
* \param pin Pin number to use as PWM
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*/
|
|
int8_t pwm_start(uint8_t timer, uint8_t ab, uint8_t port, uint8_t pin);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \brief Halts the PWM in a given GPT/timer
|
|
* \param timer General purpose timer to stop [0-3]
|
|
* \param ab Select which timer to stop (Timer A or B)
|
|
* \param port Port of the gpio port mapped to the PWM to stop
|
|
* \param pin Pin of the gpio port mapped to the PWM to stop
|
|
* \param state State to leave the pin once stopped, on (1) or off (0)
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*/
|
|
int8_t pwm_stop(uint8_t timer, uint8_t ab, uint8_t port, uint8_t pin, uint8_t state);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \brief Sets the PWM duty cycle signal direction (high/low)
|
|
* \param timer General purpose timer [0-3]
|
|
* \param ab Select which timer to use (Timer A or B)
|
|
* \param dir Direction of the PWM signal, \c PWM_SIGNAL_INVERTED or
|
|
* \c PWM_SIGNAL_STRAIGHT
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*/
|
|
int8_t pwm_set_direction(uint8_t timer, uint8_t ab, uint8_t dir);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** \brief Toggle the PWM signal direction (inverts the current duty cycle)
|
|
* \param timer General purpose timer to use [0-3]
|
|
* \param ab Select which timer to use (Timer A or B)
|
|
* \return \c PWM_SUCCESS if successful, else \c PWM_ERROR
|
|
*/
|
|
int8_t pwm_toggle_direction(uint8_t timer, uint8_t ab);
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @} */
|
|
#endif /* PWM_H_ */
|
|
/*---------------------------------------------------------------------------*/
|
|
/**
|
|
* @}
|
|
* @}
|
|
*/
|