circuitpython/ports/teensy/timer.c

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stddef.h>
#include "py/runtime.h"
#include "py/gc.h"
#include "py/mphal.h"
#include "pin.h"
#include "reg.h"
#include "timer.h"
typedef enum {
CHANNEL_MODE_PWM_NORMAL,
CHANNEL_MODE_PWM_INVERTED,
CHANNEL_MODE_OC_TIMING,
CHANNEL_MODE_OC_ACTIVE,
CHANNEL_MODE_OC_INACTIVE,
CHANNEL_MODE_OC_TOGGLE,
// CHANNEL_MODE_OC_FORCED_ACTIVE,
// CHANNEL_MODE_OC_FORCED_INACTIVE,
CHANNEL_MODE_IC,
} pyb_channel_mode;
STATIC const struct {
qstr name;
uint32_t oc_mode;
} channel_mode_info[] = {
{ MP_QSTR_PWM, FTM_OCMODE_PWM1 },
{ MP_QSTR_PWM_INVERTED, FTM_OCMODE_PWM2 },
{ MP_QSTR_OC_TIMING, FTM_OCMODE_TIMING },
{ MP_QSTR_OC_ACTIVE, FTM_OCMODE_ACTIVE },
{ MP_QSTR_OC_INACTIVE, FTM_OCMODE_INACTIVE },
{ MP_QSTR_OC_TOGGLE, FTM_OCMODE_TOGGLE },
// { MP_QSTR_OC_FORCED_ACTIVE, FTM_OCMODE_FORCED_ACTIVE },
// { MP_QSTR_OC_FORCED_INACTIVE, FTM_OCMODE_FORCED_INACTIVE },
{ MP_QSTR_IC, 0 },
};
struct _pyb_timer_obj_t;
typedef struct _pyb_timer_channel_obj_t {
mp_obj_base_t base;
struct _pyb_timer_obj_t *timer;
uint8_t channel;
uint8_t mode;
mp_obj_t callback;
struct _pyb_timer_channel_obj_t *next;
} pyb_timer_channel_obj_t;
typedef struct _pyb_timer_obj_t {
mp_obj_base_t base;
uint8_t tim_id;
uint8_t irqn;
mp_obj_t callback;
FTM_HandleTypeDef ftm;
pyb_timer_channel_obj_t *channel;
} pyb_timer_obj_t;
// Used to do callbacks to Python code on interrupt
STATIC pyb_timer_obj_t *pyb_timer_obj_all[3];
#define PYB_TIMER_OBJ_ALL_NUM MP_ARRAY_SIZE(pyb_timer_obj_all)
STATIC mp_obj_t pyb_timer_deinit(mp_obj_t self_in);
STATIC mp_obj_t pyb_timer_callback(mp_obj_t self_in, mp_obj_t callback);
STATIC mp_obj_t pyb_timer_channel_callback(mp_obj_t self_in, mp_obj_t callback);
void timer_init0(void) {
for (uint i = 0; i < PYB_TIMER_OBJ_ALL_NUM; i++) {
pyb_timer_obj_all[i] = NULL;
}
}
// unregister all interrupt sources
void timer_deinit(void) {
for (uint i = 0; i < PYB_TIMER_OBJ_ALL_NUM; i++) {
pyb_timer_obj_t *tim = pyb_timer_obj_all[i];
if (tim != NULL) {
pyb_timer_deinit(tim);
}
}
}
mp_uint_t get_prescaler_shift(mp_int_t prescaler) {
mp_uint_t prescaler_shift;
for (prescaler_shift = 0; prescaler_shift < 8; prescaler_shift++) {
if (prescaler == (1 << prescaler_shift)) {
return prescaler_shift;
}
}
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "prescaler must be a power of 2 between 1 and 128, not %d", prescaler));
}
/******************************************************************************/
/* MicroPython bindings */
STATIC const mp_obj_type_t pyb_timer_channel_type;
// Helper function for determining the period used for calculating percent
STATIC uint32_t compute_period(pyb_timer_obj_t *self) {
// In center mode, compare == period corresponds to 100%
// In edge mode, compare == (period + 1) corresponds to 100%
FTM_TypeDef *FTMx = self->ftm.Instance;
uint32_t period = (FTMx->MOD & 0xffff);
if ((FTMx->SC & FTM_SC_CPWMS) == 0) {
// Edge mode
period++;
}
return period;
}
// Helper function to compute PWM value from timer period and percent value.
// 'val' can be an int or a float between 0 and 100 (out of range values are
// clamped).
STATIC uint32_t compute_pwm_value_from_percent(uint32_t period, mp_obj_t percent_in) {
uint32_t cmp;
if (0) {
#if MICROPY_PY_BUILTINS_FLOAT
} else if (mp_obj_is_type(percent_in, &mp_type_float)) {
float percent = mp_obj_get_float(percent_in);
if (percent <= 0.0) {
cmp = 0;
} else if (percent >= 100.0) {
cmp = period;
} else {
cmp = percent / 100.0 * ((float)period);
}
#endif
} else {
mp_int_t percent = mp_obj_get_int(percent_in);
if (percent <= 0) {
cmp = 0;
} else if (percent >= 100) {
cmp = period;
} else {
cmp = ((uint32_t)percent * period) / 100;
}
}
return cmp;
}
// Helper function to compute percentage from timer perion and PWM value.
STATIC mp_obj_t compute_percent_from_pwm_value(uint32_t period, uint32_t cmp) {
#if MICROPY_PY_BUILTINS_FLOAT
float percent = (float)cmp * 100.0 / (float)period;
if (cmp >= period) {
percent = 100.0;
} else {
percent = (float)cmp * 100.0 / (float)period;
}
return mp_obj_new_float(percent);
#else
mp_int_t percent;
if (cmp >= period) {
percent = 100;
} else {
percent = cmp * 100 / period;
}
return mp_obj_new_int(percent);
#endif
}
STATIC void pyb_timer_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_timer_obj_t *self = self_in;
if (self->ftm.State == HAL_FTM_STATE_RESET) {
mp_printf(print, "Timer(%u)", self->tim_id);
} else {
mp_printf(print, "Timer(%u, prescaler=%u, period=%u, mode=%s)",
self->tim_id,
1 << (self->ftm.Instance->SC & 7),
self->ftm.Instance->MOD & 0xffff,
self->ftm.Init.CounterMode == FTM_COUNTERMODE_UP ? "UP" : "CENTER");
}
}
/// \method init(*, freq, prescaler, period)
/// Initialise the timer. Initialisation must be either by frequency (in Hz)
/// or by prescaler and period:
///
/// tim.init(freq=100) # set the timer to trigger at 100Hz
/// tim.init(prescaler=83, period=999) # set the prescaler and period directly
///
/// Keyword arguments:
///
/// - `freq` - specifies the periodic frequency of the timer. You migh also
/// view this as the frequency with which the timer goes through
/// one complete cycle.
///
/// - `prescaler` 1, 2, 4, 8 16 32, 64 or 128 - specifies the value to be loaded into the
/// timer's prescaler. The timer clock source is divided by
/// (`prescaler`) to arrive at the timer clock.
///
/// - `period` [0-0xffff] - Specifies the value to be loaded into the timer's
/// Modulo Register (MOD). This determines the period of the timer (i.e.
/// when the counter cycles). The timer counter will roll-over after
/// `period` timer clock cycles. In center mode, a compare register > 0x7fff
/// doesn't seem to work properly, so keep this in mind.
///
/// - `mode` can be one of:
/// - `Timer.UP` - configures the timer to count from 0 to MOD (default)
/// - `Timer.CENTER` - confgures the timer to count from 0 to MOD and
/// then back down to 0.
///
/// - `callback` - as per Timer.callback()
///
/// You must either specify freq or both of period and prescaler.
STATIC const mp_arg_t pyb_timer_init_args[] = {
{ MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
{ MP_QSTR_prescaler, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
{ MP_QSTR_period, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
{ MP_QSTR_mode, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = FTM_COUNTERMODE_UP} },
{ MP_QSTR_callback, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
};
#define PYB_TIMER_INIT_NUM_ARGS MP_ARRAY_SIZE(pyb_timer_init_args)
STATIC mp_obj_t pyb_timer_init_helper(pyb_timer_obj_t *self, uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
// parse args
mp_arg_val_t vals[PYB_TIMER_INIT_NUM_ARGS];
mp_arg_parse_all(n_args, args, kw_args, PYB_TIMER_INIT_NUM_ARGS, pyb_timer_init_args, vals);
FTM_HandleTypeDef *ftm = &self->ftm;
// set the TIM configuration values
FTM_Base_InitTypeDef *init = &ftm->Init;
if (vals[0].u_int != 0xffffffff) {
// set prescaler and period from frequency
if (vals[0].u_int == 0) {
mp_raise_ValueError("can't have 0 frequency");
}
uint32_t period = MAX(1, F_BUS / vals[0].u_int);
uint32_t prescaler_shift = 0;
while (period > 0xffff && prescaler_shift < 7) {
period >>= 1;
prescaler_shift++;
}
if (period > 0xffff) {
period = 0xffff;
}
init->PrescalerShift = prescaler_shift;
init->Period = period;
} else if (vals[1].u_int != 0xffffffff && vals[2].u_int != 0xffffffff) {
// set prescaler and period directly
init->PrescalerShift = get_prescaler_shift(vals[1].u_int);
init->Period = vals[2].u_int;
if (!IS_FTM_PERIOD(init->Period)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "period must be between 0 and 65535, not %d", init->Period));
}
} else {
mp_raise_TypeError("must specify either freq, or prescaler and period");
}
init->CounterMode = vals[3].u_int;
if (!IS_FTM_COUNTERMODE(init->CounterMode)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "invalid counter mode: %d", init->CounterMode));
}
// Currently core/mk20dx128.c sets SIM_SCGC6_FTM0, SIM_SCGC6_FTM1, SIM_SCGC3_FTM2
// so we don't need to do it here.
NVIC_SET_PRIORITY(self->irqn, 0xe); // next-to lowest priority
HAL_FTM_Base_Init(ftm);
if (vals[4].u_obj == mp_const_none) {
HAL_FTM_Base_Start(ftm);
} else {
pyb_timer_callback(self, vals[4].u_obj);
}
return mp_const_none;
}
/// \classmethod \constructor(id, ...)
/// Construct a new timer object of the given id. If additional
/// arguments are given, then the timer is initialised by `init(...)`.
/// `id` can be 1 to 14, excluding 3.
STATIC mp_obj_t pyb_timer_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
// check arguments
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
// create new Timer object
pyb_timer_obj_t *tim = m_new_obj(pyb_timer_obj_t);
memset(tim, 0, sizeof(*tim));
tim->base.type = &pyb_timer_type;
tim->callback = mp_const_none;
tim->channel = NULL;
// get FTM number
tim->tim_id = mp_obj_get_int(args[0]);
switch (tim->tim_id) {
case 0: tim->ftm.Instance = FTM0; tim->irqn = IRQ_FTM0; break;
case 1: tim->ftm.Instance = FTM1; tim->irqn = IRQ_FTM1; break;
case 2: tim->ftm.Instance = FTM2; tim->irqn = IRQ_FTM2; break;
default: nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Timer %d does not exist", tim->tim_id));
}
if (n_args > 1 || n_kw > 0) {
// start the peripheral
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
pyb_timer_init_helper(tim, n_args - 1, args + 1, &kw_args);
}
// set the global variable for interrupt callbacks
if (tim->tim_id < PYB_TIMER_OBJ_ALL_NUM) {
pyb_timer_obj_all[tim->tim_id] = tim;
}
return (mp_obj_t)tim;
}
STATIC mp_obj_t pyb_timer_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
return pyb_timer_init_helper(args[0], n_args - 1, args + 1, kw_args);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_timer_init_obj, 1, pyb_timer_init);
/// \method deinit()
/// Deinitialises the timer.
///
/// Disables the callback (and the associated irq).
/// Disables any channel callbacks (and the associated irq).
/// Stops the timer, and disables the timer peripheral.
STATIC mp_obj_t pyb_timer_deinit(mp_obj_t self_in) {
pyb_timer_obj_t *self = self_in;
// Disable the base interrupt
pyb_timer_callback(self_in, mp_const_none);
pyb_timer_channel_obj_t *chan = self->channel;
self->channel = NULL;
// Disable the channel interrupts
while (chan != NULL) {
pyb_timer_channel_callback(chan, mp_const_none);
pyb_timer_channel_obj_t *prev_chan = chan;
chan = chan->next;
prev_chan->next = NULL;
}
HAL_FTM_Base_DeInit(&self->ftm);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_timer_deinit_obj, pyb_timer_deinit);
/// \method channel(channel, mode, ...)
///
/// If only a channel number is passed, then a previously initialized channel
/// object is returned (or `None` if there is no previous channel).
///
/// Othwerwise, a TimerChannel object is initialized and returned.
///
/// Each channel can be configured to perform pwm, output compare, or
/// input capture. All channels share the same underlying timer, which means
/// that they share the same timer clock.
///
/// Keyword arguments:
///
/// - `mode` can be one of:
/// - `Timer.PWM` - configure the timer in PWM mode (active high).
/// - `Timer.PWM_INVERTED` - configure the timer in PWM mode (active low).
/// - `Timer.OC_TIMING` - indicates that no pin is driven.
/// - `Timer.OC_ACTIVE` - the pin will be made active when a compare
/// match occurs (active is determined by polarity)
/// - `Timer.OC_INACTIVE` - the pin will be made inactive when a compare
/// match occurs.
/// - `Timer.OC_TOGGLE` - the pin will be toggled when an compare match occurs.
/// - `Timer.IC` - configure the timer in Input Capture mode.
///
/// - `callback` - as per TimerChannel.callback()
///
/// - `pin` None (the default) or a Pin object. If specified (and not None)
/// this will cause the alternate function of the the indicated pin
/// to be configured for this timer channel. An error will be raised if
/// the pin doesn't support any alternate functions for this timer channel.
///
/// Keyword arguments for Timer.PWM modes:
///
/// - `pulse_width` - determines the initial pulse width value to use.
/// - `pulse_width_percent` - determines the initial pulse width percentage to use.
///
/// Keyword arguments for Timer.OC modes:
///
/// - `compare` - determines the initial value of the compare register.
///
/// - `polarity` can be one of:
/// - `Timer.HIGH` - output is active high
/// - `Timer.LOW` - output is acive low
///
/// Optional keyword arguments for Timer.IC modes:
///
/// - `polarity` can be one of:
/// - `Timer.RISING` - captures on rising edge.
/// - `Timer.FALLING` - captures on falling edge.
/// - `Timer.BOTH` - captures on both edges.
///
/// PWM Example:
///
/// timer = pyb.Timer(0, prescaler=128, period=37500, counter_mode=pyb.Timer.COUNTER_MODE_CENTER)
/// ch0 = t0.channel(0, pyb.Timer.PWM, pin=pyb.Pin.board.D22, pulse_width=(t0.period() + 1) // 4)
/// ch1 = t0.channel(1, pyb.Timer.PWM, pin=pyb.Pin.board.D23, pulse_width=(t0.period() + 1) // 2)
STATIC const mp_arg_t pyb_timer_channel_args[] = {
{ MP_QSTR_callback, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
{ MP_QSTR_pin, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
{ MP_QSTR_pulse_width, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_pulse_width_percent, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
{ MP_QSTR_compare, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
};
#define PYB_TIMER_CHANNEL_NUM_ARGS MP_ARRAY_SIZE(pyb_timer_channel_args)
STATIC mp_obj_t pyb_timer_channel(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
pyb_timer_obj_t *self = args[0];
mp_int_t channel = mp_obj_get_int(args[1]);
if (channel < 0 || channel > 7) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Invalid channel (%d)", channel));
}
pyb_timer_channel_obj_t *chan = self->channel;
pyb_timer_channel_obj_t *prev_chan = NULL;
while (chan != NULL) {
if (chan->channel == channel) {
break;
}
prev_chan = chan;
chan = chan->next;
}
// If only the channel number is given return the previously allocated
// channel (or None if no previous channel).
if (n_args == 2) {
if (chan) {
return chan;
}
return mp_const_none;
}
// If there was already a channel, then remove it from the list. Note that
// the order we do things here is important so as to appear atomic to
// the IRQ handler.
if (chan) {
// Turn off any IRQ associated with the channel.
pyb_timer_channel_callback(chan, mp_const_none);
// Unlink the channel from the list.
if (prev_chan) {
prev_chan->next = chan->next;
}
self->channel = chan->next;
chan->next = NULL;
}
// Allocate and initialize a new channel
mp_arg_val_t vals[PYB_TIMER_CHANNEL_NUM_ARGS];
mp_arg_parse_all(n_args - 3, args + 3, kw_args, PYB_TIMER_CHANNEL_NUM_ARGS, pyb_timer_channel_args, vals);
chan = m_new_obj(pyb_timer_channel_obj_t);
memset(chan, 0, sizeof(*chan));
chan->base.type = &pyb_timer_channel_type;
chan->timer = self;
chan->channel = channel;
chan->mode = mp_obj_get_int(args[2]);
chan->callback = vals[0].u_obj;
mp_obj_t pin_obj = vals[1].u_obj;
if (pin_obj != mp_const_none) {
if (!mp_obj_is_type(pin_obj, &pin_type)) {
mp_raise_ValueError("pin argument needs to be be a Pin type");
}
const pin_obj_t *pin = pin_obj;
const pin_af_obj_t *af = pin_find_af(pin, AF_FN_FTM, self->tim_id);
if (af == NULL) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "pin %s doesn't have an af for TIM%d", qstr_str(pin->name), self->tim_id));
}
// pin.init(mode=AF_PP, af=idx)
const mp_obj_t args[6] = {
(mp_obj_t)&pin_init_obj,
pin_obj,
MP_OBJ_NEW_QSTR(MP_QSTR_mode), MP_OBJ_NEW_SMALL_INT(GPIO_MODE_AF_PP),
MP_OBJ_NEW_QSTR(MP_QSTR_af), MP_OBJ_NEW_SMALL_INT(af->idx)
};
mp_call_method_n_kw(0, 2, args);
}
// Link the channel to the timer before we turn the channel on.
// Note that this needs to appear atomic to the IRQ handler (the write
// to self->channel is atomic, so we're good, but I thought I'd mention
// in case this was ever changed in the future).
chan->next = self->channel;
self->channel = chan;
switch (chan->mode) {
case CHANNEL_MODE_PWM_NORMAL:
case CHANNEL_MODE_PWM_INVERTED: {
FTM_OC_InitTypeDef oc_config;
oc_config.OCMode = channel_mode_info[chan->mode].oc_mode;
if (vals[3].u_obj != mp_const_none) {
// pulse width ratio given
uint32_t period = compute_period(self);
oc_config.Pulse = compute_pwm_value_from_percent(period, vals[3].u_obj);
} else {
// use absolute pulse width value (defaults to 0 if nothing given)
oc_config.Pulse = vals[2].u_int;
}
oc_config.OCPolarity = FTM_OCPOLARITY_HIGH;
HAL_FTM_PWM_ConfigChannel(&self->ftm, &oc_config, channel);
if (chan->callback == mp_const_none) {
HAL_FTM_PWM_Start(&self->ftm, channel);
} else {
HAL_FTM_PWM_Start_IT(&self->ftm, channel);
}
break;
}
case CHANNEL_MODE_OC_TIMING:
case CHANNEL_MODE_OC_ACTIVE:
case CHANNEL_MODE_OC_INACTIVE:
case CHANNEL_MODE_OC_TOGGLE: {
FTM_OC_InitTypeDef oc_config;
oc_config.OCMode = channel_mode_info[chan->mode].oc_mode;
oc_config.Pulse = vals[4].u_int;
oc_config.OCPolarity = vals[5].u_int;
if (oc_config.OCPolarity == 0xffffffff) {
oc_config.OCPolarity = FTM_OCPOLARITY_HIGH;
}
if (!IS_FTM_OC_POLARITY(oc_config.OCPolarity)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Invalid polarity (%d)", oc_config.OCPolarity));
}
HAL_FTM_OC_ConfigChannel(&self->ftm, &oc_config, channel);
if (chan->callback == mp_const_none) {
HAL_FTM_OC_Start(&self->ftm, channel);
} else {
HAL_FTM_OC_Start_IT(&self->ftm, channel);
}
break;
}
case CHANNEL_MODE_IC: {
FTM_IC_InitTypeDef ic_config;
ic_config.ICPolarity = vals[5].u_int;
if (ic_config.ICPolarity == 0xffffffff) {
ic_config.ICPolarity = FTM_ICPOLARITY_RISING;
}
if (!IS_FTM_IC_POLARITY(ic_config.ICPolarity)) {
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Invalid polarity (%d)", ic_config.ICPolarity));
}
HAL_FTM_IC_ConfigChannel(&self->ftm, &ic_config, chan->channel);
if (chan->callback == mp_const_none) {
HAL_FTM_IC_Start(&self->ftm, channel);
} else {
HAL_FTM_IC_Start_IT(&self->ftm, channel);
}
break;
}
default:
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Invalid mode (%d)", chan->mode));
}
return chan;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_timer_channel_obj, 2, pyb_timer_channel);
/// \method counter([value])
/// Get or set the timer counter.
STATIC mp_obj_t pyb_timer_counter(size_t n_args, const mp_obj_t *args) {
pyb_timer_obj_t *self = args[0];
if (n_args == 1) {
// get
return mp_obj_new_int(self->ftm.Instance->CNT);
}
// set - In order to write to CNT we need to set CNTIN
self->ftm.Instance->CNTIN = mp_obj_get_int(args[1]);
self->ftm.Instance->CNT = 0; // write any value to load CNTIN into CNT
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_counter_obj, 1, 2, pyb_timer_counter);
/// \method prescaler([value])
/// Get or set the prescaler for the timer.
STATIC mp_obj_t pyb_timer_prescaler(size_t n_args, const mp_obj_t *args) {
pyb_timer_obj_t *self = args[0];
if (n_args == 1) {
// get
return mp_obj_new_int(1 << (self->ftm.Instance->SC & 7));
}
// set
mp_uint_t prescaler_shift = get_prescaler_shift(mp_obj_get_int(args[1]));
mp_uint_t sc = self->ftm.Instance->SC;
sc &= ~7;
sc |= FTM_SC_PS(prescaler_shift);
self->ftm.Instance->SC = sc;
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_prescaler_obj, 1, 2, pyb_timer_prescaler);
/// \method period([value])
/// Get or set the period of the timer.
STATIC mp_obj_t pyb_timer_period(size_t n_args, const mp_obj_t *args) {
pyb_timer_obj_t *self = args[0];
if (n_args == 1) {
// get
return mp_obj_new_int(self->ftm.Instance->MOD & 0xffff);
}
// set
mp_int_t period = mp_obj_get_int(args[1]) & 0xffff;
self->ftm.Instance->CNT = 0;
self->ftm.Instance->MOD = period;
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_period_obj, 1, 2, pyb_timer_period);
/// \method callback(fun)
/// Set the function to be called when the timer triggers.
/// `fun` is passed 1 argument, the timer object.
/// If `fun` is `None` then the callback will be disabled.
STATIC mp_obj_t pyb_timer_callback(mp_obj_t self_in, mp_obj_t callback) {
pyb_timer_obj_t *self = self_in;
if (callback == mp_const_none) {
// stop interrupt (but not timer)
__HAL_FTM_DISABLE_TOF_IT(&self->ftm);
self->callback = mp_const_none;
} else if (mp_obj_is_callable(callback)) {
self->callback = callback;
HAL_NVIC_EnableIRQ(self->irqn);
// start timer, so that it interrupts on overflow
HAL_FTM_Base_Start_IT(&self->ftm);
} else {
mp_raise_ValueError("callback must be None or a callable object");
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_timer_callback_obj, pyb_timer_callback);
#if MICROPY_TIMER_REG
reg_t timer_reg[] = {
REG_ENTRY(FTM_TypeDef, SC),
REG_ENTRY(FTM_TypeDef, CNT),
REG_ENTRY(FTM_TypeDef, MOD),
REG_ENTRY(FTM_TypeDef, CNTIN),
REG_ENTRY(FTM_TypeDef, STATUS),
REG_ENTRY(FTM_TypeDef, MODE),
REG_ENTRY(FTM_TypeDef, SYNC),
REG_ENTRY(FTM_TypeDef, OUTINIT),
REG_ENTRY(FTM_TypeDef, OUTMASK),
REG_ENTRY(FTM_TypeDef, COMBINE),
REG_ENTRY(FTM_TypeDef, DEADTIME),
REG_ENTRY(FTM_TypeDef, EXTTRIG),
REG_ENTRY(FTM_TypeDef, POL),
REG_ENTRY(FTM_TypeDef, FMS),
REG_ENTRY(FTM_TypeDef, FILTER),
REG_ENTRY(FTM_TypeDef, FLTCTRL),
REG_ENTRY(FTM_TypeDef, QDCTRL),
REG_ENTRY(FTM_TypeDef, CONF),
REG_ENTRY(FTM_TypeDef, FLTPOL),
REG_ENTRY(FTM_TypeDef, SYNCONF),
REG_ENTRY(FTM_TypeDef, INVCTRL),
REG_ENTRY(FTM_TypeDef, SWOCTRL),
REG_ENTRY(FTM_TypeDef, PWMLOAD),
};
mp_obj_t pyb_timer_reg(uint n_args, const mp_obj_t *args) {
pyb_timer_obj_t *self = args[0];
return reg_cmd(self->ftm.Instance, timer_reg, MP_ARRAY_SIZE(timer_reg), n_args - 1, args + 1);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_reg_obj, 1, 3, pyb_timer_reg);
#endif // MICROPY_TIMER_REG
STATIC const mp_rom_map_elem_t pyb_timer_locals_dict_table[] = {
// instance methods
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_timer_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&pyb_timer_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_channel), MP_ROM_PTR(&pyb_timer_channel_obj) },
{ MP_ROM_QSTR(MP_QSTR_counter), MP_ROM_PTR(&pyb_timer_counter_obj) },
{ MP_ROM_QSTR(MP_QSTR_prescaler), MP_ROM_PTR(&pyb_timer_prescaler_obj) },
{ MP_ROM_QSTR(MP_QSTR_period), MP_ROM_PTR(&pyb_timer_period_obj) },
{ MP_ROM_QSTR(MP_QSTR_callback), MP_ROM_PTR(&pyb_timer_callback_obj) },
#if MICROPY_TIMER_REG
{ MP_ROM_QSTR(MP_QSTR_reg), MP_ROM_PTR(&pyb_timer_reg_obj) },
#endif
{ MP_ROM_QSTR(MP_QSTR_UP), MP_ROM_INT(FTM_COUNTERMODE_UP) },
{ MP_ROM_QSTR(MP_QSTR_CENTER), MP_ROM_INT(FTM_COUNTERMODE_CENTER) },
{ MP_ROM_QSTR(MP_QSTR_PWM), MP_ROM_INT(CHANNEL_MODE_PWM_NORMAL) },
{ MP_ROM_QSTR(MP_QSTR_PWM_INVERTED), MP_ROM_INT(CHANNEL_MODE_PWM_INVERTED) },
{ MP_ROM_QSTR(MP_QSTR_OC_TIMING), MP_ROM_INT(CHANNEL_MODE_OC_TIMING) },
{ MP_ROM_QSTR(MP_QSTR_OC_ACTIVE), MP_ROM_INT(CHANNEL_MODE_OC_ACTIVE) },
{ MP_ROM_QSTR(MP_QSTR_OC_INACTIVE), MP_ROM_INT(CHANNEL_MODE_OC_INACTIVE) },
{ MP_ROM_QSTR(MP_QSTR_OC_TOGGLE), MP_ROM_INT(CHANNEL_MODE_OC_TOGGLE) },
{ MP_ROM_QSTR(MP_QSTR_IC), MP_ROM_INT(CHANNEL_MODE_IC) },
{ MP_ROM_QSTR(MP_QSTR_HIGH), MP_ROM_INT(FTM_OCPOLARITY_HIGH) },
{ MP_ROM_QSTR(MP_QSTR_LOW), MP_ROM_INT(FTM_OCPOLARITY_LOW) },
{ MP_ROM_QSTR(MP_QSTR_RISING), MP_ROM_INT(FTM_ICPOLARITY_RISING) },
{ MP_ROM_QSTR(MP_QSTR_FALLING), MP_ROM_INT(FTM_ICPOLARITY_FALLING) },
{ MP_ROM_QSTR(MP_QSTR_BOTH), MP_ROM_INT(FTM_ICPOLARITY_BOTH) },
};
STATIC MP_DEFINE_CONST_DICT(pyb_timer_locals_dict, pyb_timer_locals_dict_table);
const mp_obj_type_t pyb_timer_type = {
{ &mp_type_type },
.name = MP_QSTR_Timer,
.print = pyb_timer_print,
.make_new = pyb_timer_make_new,
.locals_dict = (mp_obj_t)&pyb_timer_locals_dict,
};
/// \moduleref pyb
/// \class TimerChannel - setup a channel for a timer.
///
/// Timer channels are used to generate/capture a signal using a timer.
///
/// TimerChannel objects are created using the Timer.channel() method.
STATIC void pyb_timer_channel_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
pyb_timer_channel_obj_t *self = self_in;
mp_printf(print, "TimerChannel(timer=%u, channel=%u, mode=%s)",
self->timer->tim_id,
self->channel,
qstr_str(channel_mode_info[self->mode].name));
}
/// \method capture([value])
/// Get or set the capture value associated with a channel.
/// capture, compare, and pulse_width are all aliases for the same function.
/// capture is the logical name to use when the channel is in input capture mode.
/// \method compare([value])
/// Get or set the compare value associated with a channel.
/// capture, compare, and pulse_width are all aliases for the same function.
/// compare is the logical name to use when the channel is in output compare mode.
/// \method pulse_width([value])
/// Get or set the pulse width value associated with a channel.
/// capture, compare, and pulse_width are all aliases for the same function.
/// pulse_width is the logical name to use when the channel is in PWM mode.
///
/// In edge aligned mode, a pulse_width of `period + 1` corresponds to a duty cycle of 100%
/// In center aligned mode, a pulse width of `period` corresponds to a duty cycle of 100%
STATIC mp_obj_t pyb_timer_channel_capture_compare(size_t n_args, const mp_obj_t *args) {
pyb_timer_channel_obj_t *self = args[0];
FTM_TypeDef *FTMx = self->timer->ftm.Instance;
if (n_args == 1) {
// get
return mp_obj_new_int(FTMx->channel[self->channel].CV & 0xffff);
}
mp_int_t pw = mp_obj_get_int(args[1]);
// set
FTMx->channel[self->channel].CV = pw & 0xffff;
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_channel_capture_compare_obj, 1, 2, pyb_timer_channel_capture_compare);
/// \method pulse_width_percent([value])
/// Get or set the pulse width percentage associated with a channel. The value
/// is a number between 0 and 100 and sets the percentage of the timer period
/// for which the pulse is active. The value can be an integer or
/// floating-point number for more accuracy. For example, a value of 25 gives
/// a duty cycle of 25%.
STATIC mp_obj_t pyb_timer_channel_pulse_width_percent(size_t n_args, const mp_obj_t *args) {
pyb_timer_channel_obj_t *self = args[0];
FTM_TypeDef *FTMx = self->timer->ftm.Instance;
uint32_t period = compute_period(self->timer);
if (n_args == 1) {
// get
uint32_t cmp = FTMx->channel[self->channel].CV & 0xffff;
return compute_percent_from_pwm_value(period, cmp);
} else {
// set
uint32_t cmp = compute_pwm_value_from_percent(period, args[1]);
FTMx->channel[self->channel].CV = cmp & 0xffff;
return mp_const_none;
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_channel_pulse_width_percent_obj, 1, 2, pyb_timer_channel_pulse_width_percent);
/// \method callback(fun)
/// Set the function to be called when the timer channel triggers.
/// `fun` is passed 1 argument, the timer object.
/// If `fun` is `None` then the callback will be disabled.
STATIC mp_obj_t pyb_timer_channel_callback(mp_obj_t self_in, mp_obj_t callback) {
pyb_timer_channel_obj_t *self = self_in;
if (callback == mp_const_none) {
// stop interrupt (but not timer)
__HAL_FTM_DISABLE_CH_IT(&self->timer->ftm, self->channel);
self->callback = mp_const_none;
} else if (mp_obj_is_callable(callback)) {
self->callback = callback;
HAL_NVIC_EnableIRQ(self->timer->irqn);
// start timer, so that it interrupts on overflow
switch (self->mode) {
case CHANNEL_MODE_PWM_NORMAL:
case CHANNEL_MODE_PWM_INVERTED:
HAL_FTM_PWM_Start_IT(&self->timer->ftm, self->channel);
break;
case CHANNEL_MODE_OC_TIMING:
case CHANNEL_MODE_OC_ACTIVE:
case CHANNEL_MODE_OC_INACTIVE:
case CHANNEL_MODE_OC_TOGGLE:
HAL_FTM_OC_Start_IT(&self->timer->ftm, self->channel);
break;
case CHANNEL_MODE_IC:
HAL_FTM_IC_Start_IT(&self->timer->ftm, self->channel);
break;
}
} else {
mp_raise_ValueError("callback must be None or a callable object");
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_timer_channel_callback_obj, pyb_timer_channel_callback);
#if MICROPY_TIMER_REG
reg_t timer_channel_reg[] = {
REG_ENTRY(FTM_ChannelTypeDef, CSC),
REG_ENTRY(FTM_ChannelTypeDef, CV),
};
mp_obj_t pyb_timer_channel_reg(uint n_args, const mp_obj_t *args) {
pyb_timer_channel_obj_t *self = args[0];
return reg_cmd(&self->timer->ftm.Instance->channel[self->channel],
timer_channel_reg, MP_ARRAY_SIZE(timer_channel_reg),
n_args - 1, args + 1);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_channel_reg_obj, 1, 3, pyb_timer_channel_reg);
#endif
STATIC const mp_rom_map_elem_t pyb_timer_channel_locals_dict_table[] = {
// instance methods
{ MP_ROM_QSTR(MP_QSTR_callback), MP_ROM_PTR(&pyb_timer_channel_callback_obj) },
{ MP_ROM_QSTR(MP_QSTR_pulse_width), MP_ROM_PTR(&pyb_timer_channel_capture_compare_obj) },
{ MP_ROM_QSTR(MP_QSTR_pulse_width_percent), MP_ROM_PTR(&pyb_timer_channel_pulse_width_percent_obj) },
{ MP_ROM_QSTR(MP_QSTR_capture), MP_ROM_PTR(&pyb_timer_channel_capture_compare_obj) },
{ MP_ROM_QSTR(MP_QSTR_compare), MP_ROM_PTR(&pyb_timer_channel_capture_compare_obj) },
#if MICROPY_TIMER_REG
{ MP_ROM_QSTR(MP_QSTR_reg), MP_ROM_PTR(&pyb_timer_channel_reg_obj) },
#endif
};
STATIC MP_DEFINE_CONST_DICT(pyb_timer_channel_locals_dict, pyb_timer_channel_locals_dict_table);
STATIC const mp_obj_type_t pyb_timer_channel_type = {
{ &mp_type_type },
.name = MP_QSTR_TimerChannel,
.print = pyb_timer_channel_print,
.locals_dict = (mp_obj_t)&pyb_timer_channel_locals_dict,
};
STATIC bool ftm_handle_irq_callback(pyb_timer_obj_t *self, mp_uint_t channel, mp_obj_t callback) {
// execute callback if it's set
if (callback == mp_const_none) {
return false;
}
bool handled = false;
// When executing code within a handler we must lock the GC to prevent
// any memory allocations. We must also catch any exceptions.
gc_lock();
nlr_buf_t nlr;
if (nlr_push(&nlr) == 0) {
mp_call_function_1(callback, self);
nlr_pop();
handled = true;
} else {
// Uncaught exception; disable the callback so it doesn't run again.
self->callback = mp_const_none;
if (channel == 0xffffffff) {
printf("Uncaught exception in Timer(" UINT_FMT
") interrupt handler\n", self->tim_id);
} else {
printf("Uncaught exception in Timer(" UINT_FMT ") channel "
UINT_FMT " interrupt handler\n", self->tim_id, channel);
}
mp_obj_print_exception(&mp_plat_print, (mp_obj_t)nlr.ret_val);
}
gc_unlock();
return handled;
}
STATIC void ftm_irq_handler(uint tim_id) {
if (tim_id >= PYB_TIMER_OBJ_ALL_NUM) {
return;
}
// get the timer object
pyb_timer_obj_t *self = pyb_timer_obj_all[tim_id];
if (self == NULL) {
// timer object has not been set, so we can't do anything
printf("No timer object for id=%d\n", tim_id);
return;
}
FTM_HandleTypeDef *hftm = &self->ftm;
bool handled = false;
// Check for timer (versus timer channel) interrupt.
if (__HAL_FTM_GET_TOF_IT(hftm) && __HAL_FTM_GET_TOF_FLAG(hftm)) {
__HAL_FTM_CLEAR_TOF_FLAG(hftm);
if (ftm_handle_irq_callback(self, 0xffffffff, self->callback)) {
handled = true;
} else {
__HAL_FTM_DISABLE_TOF_IT(&self->ftm);
printf("No callback for Timer %d TOF (now disabled)\n", tim_id);
}
}
uint32_t processed = 0;
// Check to see if a timer channel interrupt is pending
pyb_timer_channel_obj_t *chan = self->channel;
while (chan != NULL) {
processed |= (1 << chan->channel);
if (__HAL_FTM_GET_CH_IT(&self->ftm, chan->channel) && __HAL_FTM_GET_CH_FLAG(&self->ftm, chan->channel)) {
__HAL_FTM_CLEAR_CH_FLAG(&self->ftm, chan->channel);
if (ftm_handle_irq_callback(self, chan->channel, chan->callback)) {
handled = true;
} else {
__HAL_FTM_DISABLE_CH_IT(&self->ftm, chan->channel);
printf("No callback for Timer %d channel %u (now disabled)\n",
self->tim_id, chan->channel);
}
}
chan = chan->next;
}
if (!handled) {
// An interrupt occurred for a channel we didn't process. Find it and
// turn it off.
for (mp_uint_t channel = 0; channel < 8; channel++) {
if ((processed & (1 << channel)) == 0) {
if (__HAL_FTM_GET_CH_FLAG(&self->ftm, channel) != 0) {
__HAL_FTM_CLEAR_CH_FLAG(&self->ftm, channel);
__HAL_FTM_DISABLE_CH_IT(&self->ftm, channel);
printf("Unhandled interrupt Timer %d channel %u (now disabled)\n",
tim_id, channel);
}
}
}
}
}
void ftm0_isr(void) {
ftm_irq_handler(0);
}
void ftm1_isr(void) {
ftm_irq_handler(1);
}
void ftm2_isr(void) {
ftm_irq_handler(2);
}