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-rw-r--r--ports/rp2/machine_pwm.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/ports/rp2/machine_pwm.c b/ports/rp2/machine_pwm.c
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+++ b/ports/rp2/machine_pwm.c
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+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020-2021 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 "py/runtime.h"
+#include "py/mphal.h"
+#include "modmachine.h"
+
+#include "hardware/clocks.h"
+#include "hardware/pwm.h"
+
+/******************************************************************************/
+// MicroPython bindings for machine.PWM
+
+const mp_obj_type_t machine_pwm_type;
+
+typedef struct _machine_pwm_obj_t {
+ mp_obj_base_t base;
+ uint8_t slice;
+ uint8_t channel;
+} machine_pwm_obj_t;
+
+STATIC machine_pwm_obj_t machine_pwm_obj[] = {
+ {{&machine_pwm_type}, 0, PWM_CHAN_A},
+ {{&machine_pwm_type}, 0, PWM_CHAN_B},
+ {{&machine_pwm_type}, 1, PWM_CHAN_A},
+ {{&machine_pwm_type}, 1, PWM_CHAN_B},
+ {{&machine_pwm_type}, 2, PWM_CHAN_A},
+ {{&machine_pwm_type}, 2, PWM_CHAN_B},
+ {{&machine_pwm_type}, 3, PWM_CHAN_A},
+ {{&machine_pwm_type}, 3, PWM_CHAN_B},
+ {{&machine_pwm_type}, 4, PWM_CHAN_A},
+ {{&machine_pwm_type}, 4, PWM_CHAN_B},
+ {{&machine_pwm_type}, 5, PWM_CHAN_A},
+ {{&machine_pwm_type}, 5, PWM_CHAN_B},
+ {{&machine_pwm_type}, 6, PWM_CHAN_A},
+ {{&machine_pwm_type}, 6, PWM_CHAN_B},
+ {{&machine_pwm_type}, 7, PWM_CHAN_A},
+ {{&machine_pwm_type}, 7, PWM_CHAN_B},
+};
+
+STATIC void machine_pwm_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
+ machine_pwm_obj_t *self = MP_OBJ_TO_PTR(self_in);
+ mp_printf(print, "<PWM slice=%u channel=%u>", self->slice, self->channel);
+}
+
+// PWM(pin)
+STATIC mp_obj_t machine_pwm_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
+ // Check number of arguments
+ mp_arg_check_num(n_args, n_kw, 1, 1, false);
+
+ // Get GPIO to connect to PWM.
+ uint32_t gpio = mp_hal_get_pin_obj(all_args[0]);
+
+ // Get static peripheral object.
+ uint slice = pwm_gpio_to_slice_num(gpio);
+ uint8_t channel = pwm_gpio_to_channel(gpio);
+ const machine_pwm_obj_t *self = &machine_pwm_obj[slice * 2 + channel];
+
+ // Select PWM function for given GPIO.
+ gpio_set_function(gpio, GPIO_FUNC_PWM);
+
+ return MP_OBJ_FROM_PTR(self);
+}
+
+STATIC mp_obj_t machine_pwm_deinit(mp_obj_t self_in) {
+ machine_pwm_obj_t *self = MP_OBJ_TO_PTR(self_in);
+ pwm_set_enabled(self->slice, false);
+ return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_pwm_deinit_obj, machine_pwm_deinit);
+
+// PWM.freq([value])
+STATIC mp_obj_t machine_pwm_freq(size_t n_args, const mp_obj_t *args) {
+ machine_pwm_obj_t *self = MP_OBJ_TO_PTR(args[0]);
+ uint32_t source_hz = clock_get_hz(clk_sys);
+ if (n_args == 1) {
+ // Get frequency.
+ uint32_t div16 = pwm_hw->slice[self->slice].div;
+ uint32_t top = pwm_hw->slice[self->slice].top;
+ uint32_t pwm_freq = 16 * source_hz / div16 / top;
+ return MP_OBJ_NEW_SMALL_INT(pwm_freq);
+ } else {
+ // Set the frequency, making "top" as large as possible for maximum resolution.
+ // Maximum "top" is set at 65534 to be able to achieve 100% duty with 65535.
+ #define TOP_MAX 65534
+ mp_int_t freq = mp_obj_get_int(args[1]);
+ uint32_t div16_top = 16 * source_hz / freq;
+ uint32_t top = 1;
+ for (;;) {
+ // Try a few small prime factors to get close to the desired frequency.
+ if (div16_top >= 16 * 5 && div16_top % 5 == 0 && top * 5 <= TOP_MAX) {
+ div16_top /= 5;
+ top *= 5;
+ } else if (div16_top >= 16 * 3 && div16_top % 3 == 0 && top * 3 <= TOP_MAX) {
+ div16_top /= 3;
+ top *= 3;
+ } else if (div16_top >= 16 * 2 && top * 2 <= TOP_MAX) {
+ div16_top /= 2;
+ top *= 2;
+ } else {
+ break;
+ }
+ }
+ if (div16_top < 16) {
+ mp_raise_ValueError(MP_ERROR_TEXT("freq too large"));
+ } else if (div16_top >= 256 * 16) {
+ mp_raise_ValueError(MP_ERROR_TEXT("freq too small"));
+ }
+ pwm_hw->slice[self->slice].div = div16_top;
+ pwm_hw->slice[self->slice].top = top;
+ return mp_const_none;
+ }
+}
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_pwm_freq_obj, 1, 2, machine_pwm_freq);
+
+// PWM.duty_u16([value])
+STATIC mp_obj_t machine_pwm_duty_u16(size_t n_args, const mp_obj_t *args) {
+ machine_pwm_obj_t *self = MP_OBJ_TO_PTR(args[0]);
+ uint32_t top = pwm_hw->slice[self->slice].top;
+ if (n_args == 1) {
+ // Get duty cycle.
+ uint32_t cc = pwm_hw->slice[self->slice].cc;
+ cc = (cc >> (self->channel ? PWM_CH0_CC_B_LSB : PWM_CH0_CC_A_LSB)) & 0xffff;
+ return MP_OBJ_NEW_SMALL_INT(cc * 65535 / (top + 1));
+ } else {
+ // Set duty cycle.
+ mp_int_t duty_u16 = mp_obj_get_int(args[1]);
+ uint32_t cc = duty_u16 * (top + 1) / 65535;
+ pwm_set_chan_level(self->slice, self->channel, cc);
+ pwm_set_enabled(self->slice, true);
+ return mp_const_none;
+ }
+}
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_pwm_duty_u16_obj, 1, 2, machine_pwm_duty_u16);
+
+// PWM.duty_ns([value])
+STATIC mp_obj_t machine_pwm_duty_ns(size_t n_args, const mp_obj_t *args) {
+ machine_pwm_obj_t *self = MP_OBJ_TO_PTR(args[0]);
+ uint32_t source_hz = clock_get_hz(clk_sys);
+ uint32_t slice_hz = 16 * source_hz / pwm_hw->slice[self->slice].div;
+ if (n_args == 1) {
+ // Get duty cycle.
+ uint32_t cc = pwm_hw->slice[self->slice].cc;
+ cc = (cc >> (self->channel ? PWM_CH0_CC_B_LSB : PWM_CH0_CC_A_LSB)) & 0xffff;
+ return MP_OBJ_NEW_SMALL_INT((uint64_t)cc * 1000000000ULL / slice_hz);
+ } else {
+ // Set duty cycle.
+ mp_int_t duty_ns = mp_obj_get_int(args[1]);
+ uint32_t cc = (uint64_t)duty_ns * slice_hz / 1000000000ULL;
+ if (cc > 65535) {
+ mp_raise_ValueError(MP_ERROR_TEXT("duty larger than period"));
+ }
+ pwm_set_chan_level(self->slice, self->channel, cc);
+ pwm_set_enabled(self->slice, true);
+ return mp_const_none;
+ }
+}
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_pwm_duty_ns_obj, 1, 2, machine_pwm_duty_ns);
+
+STATIC const mp_rom_map_elem_t machine_pwm_locals_dict_table[] = {
+ { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_pwm_deinit_obj) },
+ { MP_ROM_QSTR(MP_QSTR_freq), MP_ROM_PTR(&machine_pwm_freq_obj) },
+ { MP_ROM_QSTR(MP_QSTR_duty_u16), MP_ROM_PTR(&machine_pwm_duty_u16_obj) },
+ { MP_ROM_QSTR(MP_QSTR_duty_ns), MP_ROM_PTR(&machine_pwm_duty_ns_obj) },
+};
+STATIC MP_DEFINE_CONST_DICT(machine_pwm_locals_dict, machine_pwm_locals_dict_table);
+
+const mp_obj_type_t machine_pwm_type = {
+ { &mp_type_type },
+ .name = MP_QSTR_PWM,
+ .print = machine_pwm_print,
+ .make_new = machine_pwm_make_new,
+ .locals_dict = (mp_obj_dict_t *)&machine_pwm_locals_dict,
+};
generated by cgit v1.2.3 (git 2.25.1) at 2026-05-04 16:00:55 +0000