circuitpython/ports/mimxrt/hal/pwm_backport.h

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mimxrt: Support PWM using the FLEXPWM and QTMR modules. Frequency range 15Hz/18Hz to > 1 MHz, with decreasing resolution of the duty cycle. The basic API is supported as documentated, except that keyword parameters are accepted for both the instatiaton and the PWM.init() call. Extensions: support PWM for channel pairs. Channel pairs are declared by supplying 2-element tuples for the pins. The two channels of a pair must be the A/B channel of a FLEXPWM module. These form than a complementary pair. Additional supported keyword arguments: - center=value Defines the center position of a pulse within the pulse cycle. The align keyword is actually shortcut for center. - sync=True|False: If set to True, the channels will be synchronized to a submodule 0 channel, which has already to be enabled. - align=PWM.MIDDLE | PMW.BEGIN | PWM.END. It defines, whether synchronized channels are Center-Aligned or Edge-aligned. The channels must be either complementary a channel pair or a group of synchronized channels. It may as well be applied to a single channel, but withiout any benefit. - invert= 0..3. Controls ouput inversion of the pins. Bit 0 controls the first pin, bit 1 the second. - deadtime=time_ns time of complementary channels for delaying the rising slope. - xor=0|1|2 xor causes the output of channel A and B to be xored. If applied to a X channel, it shows the value oif A ^ B. If applied to an A or B channel, both channel show the xored signal for xor=1. For xor=2, the xored signal is split between channels A and B. See also the Reference Manual, chapter about double pulses. The behavior of xor=2 can also be achieved using the center method for locating a pulse within a clock period. The output is enabled for board pins only. CPU pins may still be used for FLEXPWM, e.g. as sync source, but the signal will not be routed to the output. That applies only to FLEXPWM pins. The use of QTMR pins which are not board pins will be rejected. As part of this commit, the _WFE() statement is removed from ticks_delay_us64() to prevent PWM glitching during calls to sleep().
2021-07-26 06:48:25 -04:00
/*
* This file is part of the MicroPython project, http://micropython.org/
*
* Copyright (c) 2015, Freescale Semiconductor, Inc.
* Copyright 2016-2017 NXP *
* Copyright (c) 2021 Robert Hammelrath
* SPDX-License-Identifier: BSD-3-Clause
*
*/
#ifndef PWM_BACKPORT_H
#define PWM_BACKPORT_H
#include "fsl_pwm.h"
#ifdef FSL_FEATURE_SOC_TMR_COUNT
#include "fsl_qtmr.h"
#endif
typedef struct _pwm_signal_param_u16
{
pwm_channels_t pwmChannel; // PWM channel being configured; PWM A or PWM B
uint16_t dutyCycle_u16; // PWM pulse width, value should be between 0 to 65536
uint16_t Center_u16; // Center of the pulse, value should be between 0 to 65536
pwm_level_select_t level; // PWM output active level select */
uint16_t deadtimeValue; // The deadtime value; only used if channel pair is operating in complementary mode
} pwm_signal_param_u16_t;
#define PWM_FULL_SCALE (65536UL)
void PWM_UpdatePwmDutycycle_u16(PWM_Type *base, pwm_submodule_t subModule,
pwm_channels_t pwmSignal, uint16_t dutyCycle, uint16_t center);
void PWM_SetupPwm_u16(PWM_Type *base, pwm_submodule_t subModule, pwm_signal_param_u16_t *chnlParams,
uint32_t pwmFreq_Hz, uint32_t srcClock_Hz, bool output_enable);
void PWM_SetupPwmx_u16(PWM_Type *base, pwm_submodule_t subModule,
uint32_t pwmFreq_Hz, uint16_t duty_cycle, uint8_t invert, uint32_t srcClock_Hz);
#ifdef FSL_FEATURE_SOC_TMR_COUNT
status_t QTMR_SetupPwm_u16(TMR_Type *base, qtmr_channel_selection_t channel, uint32_t pwmFreqHz,
uint16_t dutyCycleU16, bool outputPolarity, uint32_t srcClock_Hz, bool is_init);
#endif // FSL_FEATURE_SOC_TMR_COUNT
#endif // PWM_BACKPORT_H