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stmhal: Add pulse_width_ratio to timer channel object.
This allows to set the pulse width (for PWM mode) as a ratio relative to the period of the timer. Eg, 0.5 is a 50% duty cycle. You can set the ratio in the channel init, or using channel.pulse_width_ratio; the latter can also read the pulse width as a ratio.
1 parent becbc87 commit 0e58c58

3 files changed

Lines changed: 82 additions & 31 deletions

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‎stmhal/qstrdefsport.h‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -175,6 +175,7 @@ Q(BOTH)
175175
// for TimerChannel class
176176
Q(TimerChannel)
177177
Q(pulse_width)
178+
Q(pulse_width_ratio)
178179
Q(compare)
179180
Q(capture)
180181
Q(polarity)

‎stmhal/timer.c‎

Lines changed: 81 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -104,7 +104,7 @@ typedef enum {
104104
STATIC const struct {
105105
qstr name;
106106
uint32_t oc_mode;
107-
} gChannelMode[] = {
107+
} channel_mode_info[] = {
108108
{ MP_QSTR_PWM, TIM_OCMODE_PWM1 },
109109
{ MP_QSTR_PWM_INVERTED, TIM_OCMODE_PWM2 },
110110
{ MP_QSTR_OC_TIMING, TIM_OCMODE_TIMING },
@@ -147,7 +147,7 @@ TIM_HandleTypeDef TIM5_Handle;
147147
TIM_HandleTypeDef TIM6_Handle;
148148

149149
// Used to divide down TIM3 and periodically call the flash storage IRQ
150-
static uint32_t tim3_counter = 0;
150+
STATIC uint32_t tim3_counter = 0;
151151

152152
// Used to do callbacks to Python code on interrupt
153153
STATIC pyb_timer_obj_t *pyb_timer_obj_all[14];
@@ -266,6 +266,8 @@ void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim) {
266266
/******************************************************************************/
267267
/* Micro Python bindings */
268268

269+
STATIC const mp_obj_type_t pyb_timer_channel_type;
270+
269271
STATIC void pyb_timer_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
270272
pyb_timer_obj_t *self = self_in;
271273

@@ -507,8 +509,8 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_timer_deinit_obj, pyb_timer_deinit);
507509

508510
/// \method channel(channel, mode, ...)
509511
///
510-
/// If only a channel nunber is passed, then a previously initialized channel
511-
/// object is returned.
512+
/// If only a channel number is passed, then a previously initialized channel
513+
/// object is returned (or `None` if there is no previous channel).
512514
///
513515
/// Othwerwise, a TimerChannel object is initialized and returned.
514516
///
@@ -540,7 +542,8 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_timer_deinit_obj, pyb_timer_deinit);
540542
///
541543
/// Keyword arguments for Timer.PWM modes:
542544
///
543-
/// - 'pulse_width' - determines the initial pulse width to use.
545+
/// - `pulse_width` - determines the initial pulse width value to use.
546+
/// - `pulse_width_ratio` - determines the initial pulse width ratio to use.
544547
///
545548
/// Keyword arguments for Timer.OC modes:
546549
///
@@ -563,17 +566,16 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_timer_deinit_obj, pyb_timer_deinit);
563566
/// ch2 = timer.channel(2, pyb.Timer.PWM, pin=pyb.Pin.board.X2, pulse_width=210000)
564567
/// ch3 = timer.channel(3, pyb.Timer.PWM, pin=pyb.Pin.board.X3, pulse_width=420000)
565568
STATIC const mp_arg_t pyb_timer_channel_args[] = {
566-
{ MP_QSTR_callback, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
567-
{ MP_QSTR_pin, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
568-
{ MP_QSTR_pulse_width, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
569-
{ MP_QSTR_compare, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
570-
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
569+
{ MP_QSTR_callback, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
570+
{ MP_QSTR_pin, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
571+
{ MP_QSTR_pulse_width, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
572+
{ MP_QSTR_pulse_width_ratio, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
573+
{ MP_QSTR_compare, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
574+
{ MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0xffffffff} },
571575
};
572576
#define PYB_TIMER_CHANNEL_NUM_ARGS MP_ARRAY_SIZE(pyb_timer_channel_args)
573577

574578
STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
575-
mp_arg_check_num(n_args, n_args - 3, 3, MP_OBJ_FUN_ARGS_MAX, true);
576-
577579
pyb_timer_obj_t *self = args[0];
578580
mp_int_t channel = mp_obj_get_int(args[1]);
579581

@@ -591,8 +593,10 @@ STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map
591593
prev_chan = chan;
592594
chan = chan->next;
593595
}
594-
if (kw_args->used == 0) {
595-
// Return the previously allocated channel
596+
597+
// If only the channel number is given return the previously allocated
598+
// channel (or None if no previous channel).
599+
if (n_args == 2) {
596600
if (chan) {
597601
return chan;
598602
}
@@ -658,8 +662,24 @@ STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map
658662
case CHANNEL_MODE_PWM_NORMAL:
659663
case CHANNEL_MODE_PWM_INVERTED: {
660664
TIM_OC_InitTypeDef oc_config;
661-
oc_config.OCMode = gChannelMode[chan->mode].oc_mode;
662-
oc_config.Pulse = vals[2].u_int;
665+
oc_config.OCMode = channel_mode_info[chan->mode].oc_mode;
666+
if (vals[2].u_int != 0xffffffff) {
667+
// absolute pulse width value given
668+
oc_config.Pulse = vals[2].u_int;
669+
} else if (vals[3].u_obj != mp_const_none) {
670+
// pulse width ratio given
671+
uint32_t period = (__HAL_TIM_GetAutoreload(&self->tim) & TIMER_CNT_MASK(self)) + 1;
672+
uint32_t cmp = mp_obj_get_float(vals[3].u_obj) * period;
673+
if (cmp < 0) {
674+
cmp = 0;
675+
} else if (cmp > period) {
676+
cmp = period;
677+
}
678+
oc_config.Pulse = cmp;
679+
} else {
680+
// nothing given, default to pulse width of 0
681+
oc_config.Pulse = 0;
682+
}
663683
oc_config.OCPolarity = TIM_OCPOLARITY_HIGH;
664684
oc_config.OCNPolarity = TIM_OCNPOLARITY_HIGH;
665685
oc_config.OCFastMode = TIM_OCFAST_DISABLE;
@@ -682,9 +702,9 @@ STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map
682702
case CHANNEL_MODE_OC_FORCED_ACTIVE:
683703
case CHANNEL_MODE_OC_FORCED_INACTIVE: {
684704
TIM_OC_InitTypeDef oc_config;
685-
oc_config.OCMode = gChannelMode[chan->mode].oc_mode;
686-
oc_config.Pulse = vals[3].u_int;
687-
oc_config.OCPolarity = vals[4].u_int;
705+
oc_config.OCMode = channel_mode_info[chan->mode].oc_mode;
706+
oc_config.Pulse = vals[4].u_int;
707+
oc_config.OCPolarity = vals[5].u_int;
688708
if (oc_config.OCPolarity == 0xffffffff) {
689709
oc_config.OCPolarity = TIM_OCPOLARITY_HIGH;
690710
}
@@ -708,7 +728,7 @@ STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map
708728
case CHANNEL_MODE_IC: {
709729
TIM_IC_InitTypeDef ic_config;
710730

711-
ic_config.ICPolarity = vals[4].u_int;
731+
ic_config.ICPolarity = vals[5].u_int;
712732
if (ic_config.ICPolarity == 0xffffffff) {
713733
ic_config.ICPolarity = TIM_ICPOLARITY_RISING;
714734
}
@@ -734,11 +754,11 @@ STATIC mp_obj_t pyb_timer_channel(mp_uint_t n_args, const mp_obj_t *args, mp_map
734754

735755
return chan;
736756
}
737-
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_timer_channel_obj, 3, pyb_timer_channel);
757+
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_timer_channel_obj, 2, pyb_timer_channel);
738758

739759
/// \method counter([value])
740760
/// Get or set the timer counter.
741-
mp_obj_t pyb_timer_counter(mp_uint_t n_args, const mp_obj_t *args) {
761+
STATIC mp_obj_t pyb_timer_counter(mp_uint_t n_args, const mp_obj_t *args) {
742762
pyb_timer_obj_t *self = args[0];
743763
if (n_args == 1) {
744764
// get
@@ -753,7 +773,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_counter_obj, 1, 2, pyb_time
753773

754774
/// \method prescaler([value])
755775
/// Get or set the prescaler for the timer.
756-
mp_obj_t pyb_timer_prescaler(mp_uint_t n_args, const mp_obj_t *args) {
776+
STATIC mp_obj_t pyb_timer_prescaler(mp_uint_t n_args, const mp_obj_t *args) {
757777
pyb_timer_obj_t *self = args[0];
758778
if (n_args == 1) {
759779
// get
@@ -768,7 +788,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_prescaler_obj, 1, 2, pyb_ti
768788

769789
/// \method period([value])
770790
/// Get or set the period of the timer.
771-
mp_obj_t pyb_timer_period(mp_uint_t n_args, const mp_obj_t *args) {
791+
STATIC mp_obj_t pyb_timer_period(mp_uint_t n_args, const mp_obj_t *args) {
772792
pyb_timer_obj_t *self = args[0];
773793
if (n_args == 1) {
774794
// get
@@ -852,7 +872,7 @@ STATIC void pyb_timer_channel_print(void (*print)(void *env, const char *fmt, ..
852872
print(env, "TimerChannel(timer=%u, channel=%u, mode=%s)",
853873
self->timer->tim_id,
854874
self->channel,
855-
qstr_str(gChannelMode[self->mode].name));
875+
qstr_str(channel_mode_info[self->mode].name));
856876
}
857877

858878
/// \method capture([value])
@@ -869,7 +889,7 @@ STATIC void pyb_timer_channel_print(void (*print)(void *env, const char *fmt, ..
869889
/// Get or set the pulse width value associated with a channel.
870890
/// capture, compare, and pulse_width are all aliases for the same function.
871891
/// pulse_width is the logical name to use when the channel is in PWM mode.
872-
STATIC mp_obj_t pyb_timer_channel_capture_compare(uint n_args, const mp_obj_t *args) {
892+
STATIC mp_obj_t pyb_timer_channel_capture_compare(mp_uint_t n_args, const mp_obj_t *args) {
873893
pyb_timer_channel_obj_t *self = args[0];
874894
if (self->channel == 0) {
875895
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Timer %d no channel specified", self->timer->tim_id));
@@ -885,6 +905,35 @@ STATIC mp_obj_t pyb_timer_channel_capture_compare(uint n_args, const mp_obj_t *a
885905
}
886906
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_channel_capture_compare_obj, 1, 2, pyb_timer_channel_capture_compare);
887907

908+
/// \method pulse_width_ratio([value])
909+
/// Get or set the pulse width ratio associated with a channel. The value is
910+
/// a floating-point number between 0.0 and 1.0, and is relative to the period
911+
/// of the timer associated with this channel. For example, a ratio of 0.5
912+
/// would be a 50% duty cycle.
913+
STATIC mp_obj_t pyb_timer_channel_pulse_width_ratio(mp_uint_t n_args, const mp_obj_t *args) {
914+
pyb_timer_channel_obj_t *self = args[0];
915+
if (self->channel == 0) {
916+
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Timer %d no channel specified", self->timer->tim_id));
917+
}
918+
uint32_t period = (__HAL_TIM_GetAutoreload(&self->timer->tim) & TIMER_CNT_MASK(self->timer)) + 1;
919+
if (n_args == 1) {
920+
// get
921+
uint32_t cmp = __HAL_TIM_GetCompare(&self->timer->tim, TIMER_CHANNEL(self)) & TIMER_CNT_MASK(self->timer);
922+
return mp_obj_new_float((float)cmp / (float)period);
923+
} else {
924+
// set
925+
uint32_t cmp = mp_obj_get_float(args[1]) * period;
926+
if (cmp < 0) {
927+
cmp = 0;
928+
} else if (cmp > period) {
929+
cmp = period;
930+
}
931+
__HAL_TIM_SetCompare(&self->timer->tim, TIMER_CHANNEL(self), cmp & TIMER_CNT_MASK(self->timer));
932+
return mp_const_none;
933+
}
934+
}
935+
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_timer_channel_pulse_width_ratio_obj, 1, 2, pyb_timer_channel_pulse_width_ratio);
936+
888937
/// \method callback(fun)
889938
/// Set the function to be called when the timer channel triggers.
890939
/// `fun` is passed 1 argument, the timer object.
@@ -927,19 +976,20 @@ STATIC const mp_map_elem_t pyb_timer_channel_locals_dict_table[] = {
927976
// instance methods
928977
{ MP_OBJ_NEW_QSTR(MP_QSTR_callback), (mp_obj_t)&pyb_timer_channel_callback_obj },
929978
{ MP_OBJ_NEW_QSTR(MP_QSTR_pulse_width), (mp_obj_t)&pyb_timer_channel_capture_compare_obj },
979+
{ MP_OBJ_NEW_QSTR(MP_QSTR_pulse_width_ratio), (mp_obj_t)&pyb_timer_channel_pulse_width_ratio_obj },
930980
{ MP_OBJ_NEW_QSTR(MP_QSTR_capture), (mp_obj_t)&pyb_timer_channel_capture_compare_obj },
931981
{ MP_OBJ_NEW_QSTR(MP_QSTR_compare), (mp_obj_t)&pyb_timer_channel_capture_compare_obj },
932982
};
933983
STATIC MP_DEFINE_CONST_DICT(pyb_timer_channel_locals_dict, pyb_timer_channel_locals_dict_table);
934984

935-
const mp_obj_type_t pyb_timer_channel_type = {
985+
STATIC const mp_obj_type_t pyb_timer_channel_type = {
936986
{ &mp_type_type },
937987
.name = MP_QSTR_TimerChannel,
938988
.print = pyb_timer_channel_print,
939989
.locals_dict = (mp_obj_t)&pyb_timer_channel_locals_dict,
940990
};
941991

942-
void timer_handle_irq_channel(pyb_timer_obj_t *tim, uint8_t channel, mp_obj_t callback) {
992+
STATIC void timer_handle_irq_channel(pyb_timer_obj_t *tim, uint8_t channel, mp_obj_t callback) {
943993
uint32_t irq_mask = TIMER_IRQ_MASK(channel);
944994

945995
if (__HAL_TIM_GET_FLAG(&tim->tim, irq_mask) != RESET) {
@@ -981,8 +1031,9 @@ void timer_irq_handler(uint tim_id) {
9811031
pyb_timer_obj_t *tim = pyb_timer_obj_all[tim_id - 1];
9821032

9831033
if (tim == NULL) {
984-
// timer object has not been set, so we can't do anything
985-
printf("No timer object for id=%d\n", tim_id);
1034+
// Timer object has not been set, so we can't do anything.
1035+
// This can happen under normal circumstances for timers like
1036+
// 1 & 10 which use the same IRQ.
9861037
return;
9871038
}
9881039

‎stmhal/timer.h‎

Lines changed: 0 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -34,7 +34,6 @@ extern TIM_HandleTypeDef TIM5_Handle;
3434
extern TIM_HandleTypeDef TIM6_Handle;
3535

3636
extern const mp_obj_type_t pyb_timer_type;
37-
extern const mp_obj_type_t pyb_timer_channel_type;
3837

3938
void timer_init0(void);
4039
void timer_tim3_init(void);

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