426 lines
15 KiB
C
426 lines
15 KiB
C
/*
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* This file is part of the MicroPython project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2016-2021 Damien P. George
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* Copyright (c) 2022 Renesas Electronics Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <stdio.h>
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#include <stdint.h>
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#include <string.h>
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#include "py/runtime.h"
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#include "py/mphal.h"
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#include "shared/runtime/mpirq.h"
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#include "modmachine.h"
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#include "extmod/virtpin.h"
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#include "pin.h"
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#include "extint.h"
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void machine_pin_init(void) {
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}
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void machine_pin_deinit(void) {
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}
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// C API used to convert a user-supplied pin name into an ordinal pin number.
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const machine_pin_obj_t *machine_pin_find(mp_obj_t user_obj) {
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const machine_pin_obj_t *pin_obj;
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// If a pin was provided, then use it
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if (mp_obj_is_type(user_obj, &machine_pin_type)) {
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pin_obj = MP_OBJ_TO_PTR(user_obj);
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return pin_obj;
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}
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// See if the pin name matches a board pin
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pin_obj = pin_find_named_pin(&pin_board_pins_locals_dict, user_obj);
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if (pin_obj) {
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return pin_obj;
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}
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// See if the pin name matches a cpu pin
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pin_obj = pin_find_named_pin(&pin_cpu_pins_locals_dict, user_obj);
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if (pin_obj) {
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return pin_obj;
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}
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("Pin(%s) doesn't exist"), mp_obj_str_get_str(user_obj));
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}
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/// Return a string describing the pin object.
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STATIC void machine_pin_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(self_in);
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// pin name
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mp_printf(print, "Pin(Pin.cpu.%q, mode=Pin.", self->name);
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uint32_t mode = pin_get_mode(self);
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if (mode == MP_HAL_PIN_MODE_ANALOG) {
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// analog
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mp_print_str(print, "ANALOG)");
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} else {
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// IO mode
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bool af = false;
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qstr mode_qst;
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if (mode == MP_HAL_PIN_MODE_INPUT) {
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mode_qst = MP_QSTR_IN;
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} else if (mode == MP_HAL_PIN_MODE_OUTPUT) {
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mode_qst = MP_QSTR_OUT;
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} else if (mode == MP_HAL_PIN_MODE_OPEN_DRAIN) {
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mode_qst = MP_QSTR_OPEN_DRAIN;
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} else {
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af = true;
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if (mode == MP_HAL_PIN_MODE_ALT) {
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mode_qst = MP_QSTR_ALT;
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} else {
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mode_qst = MP_QSTR_ALT_OPEN_DRAIN;
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}
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}
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mp_print_str(print, qstr_str(mode_qst));
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// pull mode
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qstr pull_qst = MP_QSTRnull;
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uint32_t pull = pin_get_pull(self);
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if (pull == MP_HAL_PIN_PULL_UP) {
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pull_qst = MP_QSTR_PULL_UP;
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} else if (pull == MP_HAL_PIN_PULL_NONE) {
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pull_qst = MP_QSTR_PULL_NONE;
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}
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if (pull_qst != MP_QSTRnull) {
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mp_printf(print, ", pull=Pin.%q", pull_qst);
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}
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// drive
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qstr drive_qst = MP_QSTRnull;
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uint32_t drive = pin_get_drive(self);
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if (drive == MP_HAL_PIN_DRIVE_3) {
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drive_qst = MP_QSTR_DRIVE_3;
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} else if (drive == MP_HAL_PIN_DRIVE_2) {
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drive_qst = MP_QSTR_DRIVE_2;
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} else if (drive == MP_HAL_PIN_DRIVE_1) {
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drive_qst = MP_QSTR_DRIVE_1;
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} else if (drive == MP_HAL_PIN_DRIVE_0) {
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drive_qst = MP_QSTR_DRIVE_0;
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}
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if (drive_qst != MP_QSTRnull) {
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mp_printf(print, ", drive=Pin.%q", drive_qst);
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}
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// AF mode
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if (af) {
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mp_uint_t af_idx = pin_get_af(self);
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const pin_af_obj_t *af_obj = pin_find_af_by_index(self, af_idx);
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if (af_obj == NULL) {
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mp_printf(print, ", alt=%d)", af_idx);
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} else {
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mp_printf(print, ", alt=Pin.%q)", af_obj->name);
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}
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} else {
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mp_print_str(print, ")");
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}
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}
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}
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// pin.init(mode=-1, pull=-1, *, value=None, drive=0, alt=-1)
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STATIC mp_obj_t machine_pin_obj_init_helper(const machine_pin_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_mode, ARG_pull, ARG_value, ARG_drive, ARG_alt };
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static const mp_arg_t allowed_args[] = {
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{ MP_QSTR_mode, MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE}},
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{ MP_QSTR_pull, MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE}},
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{ MP_QSTR_value, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE}},
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{ MP_QSTR_drive, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE}},
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{ MP_QSTR_alt, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1}},
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};
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// parse args
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mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
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mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
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// get io mode
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uint32_t mode;
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if (args[ARG_mode].u_obj != mp_const_none) {
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mode = mp_obj_get_int(args[ARG_mode].u_obj);
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if (!IS_GPIO_MODE(mode)) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("invalid pin mode: %d"), mode);
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}
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} else {
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mode = ra_gpio_get_mode(self->pin);
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}
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// get pull mode
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uint32_t pull;
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if (args[ARG_pull].u_obj != mp_const_none) {
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pull = mp_obj_get_int(args[ARG_pull].u_obj);
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if (!IS_GPIO_PULL(pull)) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("invalid pull mode: %d"), pull);
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}
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if (pull == MP_HAL_PIN_PULL_DOWN) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("%q is not supported"), MP_QSTR_PULL_DOWN);
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}
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} else {
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pull = ra_gpio_get_pull(self->pin);
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}
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// get drive
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uint32_t drive;
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if (args[ARG_drive].u_obj != mp_const_none) {
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drive = mp_obj_get_int(args[ARG_drive].u_obj);
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if (!IS_GPIO_DRIVE(drive)) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("invalid pin drive: %d"), drive);
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}
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} else {
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drive = ra_gpio_get_drive(self->pin);
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}
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// get alt
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if (args[ARG_alt].u_int != (-1)) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("alt is not supported"));
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}
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mp_hal_pin_config(self, mode, pull, drive, 0);
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// if given, set the pin value before initialising to prevent glitches
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if (args[ARG_value].u_obj != mp_const_none) {
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mp_hal_pin_write(self, mp_obj_is_true(args[ARG_value].u_obj));
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}
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return mp_const_none;
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}
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// constructor(id, ...)
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mp_obj_t mp_pin_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
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mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
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// Run an argument through the mapper and return the result.
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const machine_pin_obj_t *pin = machine_pin_find(args[0]);
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if (n_args > 1 || n_kw > 0) {
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// pin mode given, so configure this GPIO
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mp_map_t kw_args;
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mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
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machine_pin_obj_init_helper(pin, n_args - 1, args + 1, &kw_args);
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}
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return MP_OBJ_FROM_PTR(pin);
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}
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// fast method for getting/setting pin value
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STATIC mp_obj_t machine_pin_call(mp_obj_t self_in, size_t n_args, size_t n_kw, const mp_obj_t *args) {
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mp_arg_check_num(n_args, n_kw, 0, 1, false);
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(self_in);
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if (n_args == 0) {
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// get pin
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return MP_OBJ_NEW_SMALL_INT(mp_hal_pin_read(self));
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} else {
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// set pin
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mp_hal_pin_write(self, mp_obj_is_true(args[0]));
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return mp_const_none;
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}
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}
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// pin.init(mode, pull)
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STATIC mp_obj_t machine_pin_obj_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
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return machine_pin_obj_init_helper(args[0], n_args - 1, args + 1, kw_args);
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}
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MP_DEFINE_CONST_FUN_OBJ_KW(machine_pin_init_obj, 1, machine_pin_obj_init);
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// pin.value([value])
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STATIC mp_obj_t machine_pin_value(size_t n_args, const mp_obj_t *args) {
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return machine_pin_call(args[0], n_args - 1, 0, args + 1);
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_pin_value_obj, 1, 2, machine_pin_value);
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// pin.low()
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STATIC mp_obj_t machine_pin_low(mp_obj_t self_in) {
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_hal_pin_write(self, false);
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return mp_const_none;
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_pin_low_obj, machine_pin_low);
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// pin.high()
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STATIC mp_obj_t machine_pin_high(mp_obj_t self_in) {
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(self_in);
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mp_hal_pin_write(self, true);
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return mp_const_none;
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_pin_high_obj, machine_pin_high);
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// pin.irq(handler=None, trigger=IRQ_FALLING|IRQ_RISING, hard=False)
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STATIC mp_obj_t machine_pin_irq(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
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enum { ARG_handler, ARG_trigger, ARG_hard };
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static const mp_arg_t allowed_args[] = {
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{ MP_QSTR_handler, MP_ARG_OBJ, {.u_rom_obj = MP_ROM_NONE} },
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{ MP_QSTR_trigger, MP_ARG_INT, {.u_int = MP_HAL_PIN_TRIGGER_RISING | MP_HAL_PIN_TRIGGER_FALLING} },
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{ MP_QSTR_hard, MP_ARG_BOOL, {.u_bool = false} },
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};
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
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mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
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mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
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if (args[ARG_trigger].u_int & MP_HAL_PIN_TRIGGER_HIGHLEVEL) {
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mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("%q is not supported"), MP_QSTR_IRQ_HIGH_LEVEL);
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}
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if (n_args > 1 || kw_args->used != 0) {
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// configure irq
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extint_register_pin(self, args[ARG_trigger].u_int,
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args[ARG_hard].u_bool, args[ARG_handler].u_obj);
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}
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// TODO should return an IRQ object
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return mp_const_none;
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}
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STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_pin_irq_obj, 1, machine_pin_irq);
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STATIC const mp_rom_map_elem_t machine_pin_locals_dict_table[] = {
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// instance methods
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{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_pin_init_obj) },
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{ MP_ROM_QSTR(MP_QSTR_value), MP_ROM_PTR(&machine_pin_value_obj) },
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{ MP_ROM_QSTR(MP_QSTR_on), MP_ROM_PTR(&machine_pin_high_obj) },
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{ MP_ROM_QSTR(MP_QSTR_off), MP_ROM_PTR(&machine_pin_low_obj) },
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{ MP_ROM_QSTR(MP_QSTR_irq), MP_ROM_PTR(&machine_pin_irq_obj) },
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{ MP_ROM_QSTR(MP_QSTR_low), MP_ROM_PTR(&machine_pin_low_obj) },
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{ MP_ROM_QSTR(MP_QSTR_high), MP_ROM_PTR(&machine_pin_high_obj) },
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// class attributes
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{ MP_ROM_QSTR(MP_QSTR_board), MP_ROM_PTR(&pin_board_pins_obj_type) },
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{ MP_ROM_QSTR(MP_QSTR_cpu), MP_ROM_PTR(&pin_cpu_pins_obj_type) },
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// class constants
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{ MP_ROM_QSTR(MP_QSTR_IN), MP_ROM_INT(MP_HAL_PIN_MODE_INPUT) },
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{ MP_ROM_QSTR(MP_QSTR_OUT), MP_ROM_INT(MP_HAL_PIN_MODE_OUTPUT) },
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{ MP_ROM_QSTR(MP_QSTR_OPEN_DRAIN), MP_ROM_INT(MP_HAL_PIN_MODE_OPEN_DRAIN) },
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{ MP_ROM_QSTR(MP_QSTR_ALT), MP_ROM_INT(MP_HAL_PIN_MODE_ALT) },
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{ MP_ROM_QSTR(MP_QSTR_ALT_OPEN_DRAIN), MP_ROM_INT(MP_HAL_PIN_MODE_ALT_OPEN_DRAIN) },
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{ MP_ROM_QSTR(MP_QSTR_ANALOG), MP_ROM_INT(MP_HAL_PIN_MODE_ANALOG) },
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{ MP_ROM_QSTR(MP_QSTR_PULL_NONE), MP_ROM_INT(MP_HAL_PIN_PULL_NONE) },
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{ MP_ROM_QSTR(MP_QSTR_PULL_UP), MP_ROM_INT(MP_HAL_PIN_PULL_UP) },
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{ MP_ROM_QSTR(MP_QSTR_PULL_DOWN), MP_ROM_INT(MP_HAL_PIN_PULL_DOWN) },
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{ MP_ROM_QSTR(MP_QSTR_DRIVE_0), MP_ROM_INT(MP_HAL_PIN_DRIVE_0) },
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{ MP_ROM_QSTR(MP_QSTR_DRIVE_1), MP_ROM_INT(MP_HAL_PIN_DRIVE_1) },
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{ MP_ROM_QSTR(MP_QSTR_DRIVE_2), MP_ROM_INT(MP_HAL_PIN_DRIVE_2) },
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{ MP_ROM_QSTR(MP_QSTR_DRIVE_3), MP_ROM_INT(MP_HAL_PIN_DRIVE_3) },
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{ MP_ROM_QSTR(MP_QSTR_IRQ_FALLING), MP_ROM_INT(MP_HAL_PIN_TRIGGER_FALLING) },
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{ MP_ROM_QSTR(MP_QSTR_IRQ_RISING), MP_ROM_INT(MP_HAL_PIN_TRIGGER_RISING) },
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{ MP_ROM_QSTR(MP_QSTR_IRQ_LOW_LEVEL), MP_ROM_INT(MP_HAL_PIN_TRIGGER_LOWLEVEL) },
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{ MP_ROM_QSTR(MP_QSTR_IRQ_HIGH_LEVEL), MP_ROM_INT(MP_HAL_PIN_TRIGGER_HIGHLEVEL) },
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};
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STATIC MP_DEFINE_CONST_DICT(machine_pin_locals_dict, machine_pin_locals_dict_table);
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STATIC mp_uint_t machine_pin_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
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(void)errcode;
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machine_pin_obj_t *self = MP_OBJ_TO_PTR(self_in);
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switch (request) {
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case MP_PIN_READ: {
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return mp_hal_pin_read(self);
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}
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case MP_PIN_WRITE: {
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mp_hal_pin_write(self, arg);
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return 0;
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}
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}
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return -1;
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}
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STATIC const mp_pin_p_t machine_pin_pin_p = {
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.ioctl = machine_pin_ioctl,
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};
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MP_DEFINE_CONST_OBJ_TYPE(
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machine_pin_type,
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MP_QSTR_Pin,
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MP_TYPE_FLAG_NONE,
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mp_pin_make_new,
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locals_dict, &machine_pin_locals_dict,
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print, machine_pin_print,
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call, machine_pin_call,
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protocol, &machine_pin_pin_p
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);
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// Returns the pin mode. This value returned by this macro should be one of:
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// GPIO_MODE_INPUT, GPIO_MODE_OUTPUT_PP, GPIO_MODE_OUTPUT_OD,
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// GPIO_MODE_AF_PP, GPIO_MODE_AF_OD, or GPIO_MODE_ANALOG.
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uint32_t pin_get_mode(const machine_pin_obj_t *pin) {
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return ra_gpio_get_mode(pin->pin);
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}
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// Returns the pin pullup/pulldown. The value returned by this macro should
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// be one of GPIO_NOPULL, GPIO_PULLUP, or GPIO_PULLDOWN.
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uint32_t pin_get_pull(const machine_pin_obj_t *pin) {
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return (uint32_t)ra_gpio_get_pull(pin->pin);
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}
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// Returns the pin drive. The value returned by this macro should
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// be one of GPIO_HIGH_POWER, GPIO_MID_FAST_POWER, GPIO_MID_POWER,
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// or GPIO_LOW_POWER.
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uint32_t pin_get_drive(const machine_pin_obj_t *pin) {
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return (uint32_t)ra_gpio_get_drive(pin->pin);
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}
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// Returns the af (alternate function) index currently set for a pin.
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uint32_t pin_get_af(const machine_pin_obj_t *pin) {
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return (uint32_t)ra_gpio_get_af(pin->pin);
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}
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MP_DEFINE_CONST_OBJ_TYPE(
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pin_cpu_pins_obj_type,
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MP_QSTR_cpu,
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MP_TYPE_FLAG_NONE,
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MP_TYPE_NULL_MAKE_NEW,
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locals_dict, &pin_cpu_pins_locals_dict
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);
|
|
|
|
MP_DEFINE_CONST_OBJ_TYPE(
|
|
pin_board_pins_obj_type,
|
|
MP_QSTR_board,
|
|
MP_TYPE_FLAG_NONE,
|
|
MP_TYPE_NULL_MAKE_NEW,
|
|
locals_dict, &pin_board_pins_locals_dict
|
|
);
|
|
|
|
const machine_pin_obj_t *pin_find_named_pin(const mp_obj_dict_t *named_pins, mp_obj_t name) {
|
|
const mp_map_t *named_map = &named_pins->map;
|
|
mp_map_elem_t *named_elem = mp_map_lookup((mp_map_t *)named_map, name, MP_MAP_LOOKUP);
|
|
if (named_elem != NULL && named_elem->value != MP_OBJ_NULL) {
|
|
return MP_OBJ_TO_PTR(named_elem->value);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
const pin_af_obj_t *pin_find_af_by_index(const machine_pin_obj_t *pin, mp_uint_t af_idx) {
|
|
const pin_af_obj_t *af = pin->af;
|
|
for (mp_uint_t i = 0; i < pin->num_af; i++, af++) {
|
|
if (af->idx == af_idx) {
|
|
return af;
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|