circuitpython/shared-bindings/bitbangio/OneWire.c

168 lines
6.3 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
*
* 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 <stdint.h>
#include "lib/utils/context_manager_helpers.h"
#include "py/objproperty.h"
#include "py/runtime.h"
#include "py/runtime0.h"
#include "shared-bindings/microcontroller/Pin.h"
#include "shared-bindings/bitbangio/OneWire.h"
//| .. currentmodule:: bitbangio
//|
//| :class:`OneWire` -- Lowest-level of the Maxim OneWire protocol
//| ===============================================================
//|
//| :class:`~bitbangio.OneWire` implements the timing-sensitive foundation of
//| the Maxim (formerly Dallas Semi) OneWire protocol.
//|
//| Protocol definition is here: https://www.maximintegrated.com/en/app-notes/index.mvp/id/126
//|
//| .. class:: OneWire(pin)
//|
//| Create a OneWire object associated with the given pin. The object
//| implements the lowest level timing-sensitive bits of the protocol.
//|
//| :param ~microcontroller.Pin pin: Pin to read pulses from.
//|
//| Read a short series of pulses::
//|
//| import bitbangio
//| import board
//|
//| onewire = bitbangio.OneWire(board.D7)
//| onewire.reset()
//| onewire.write_bit(True)
//| onewire.write_bit(False)
//| print(onewire.read_bit())
//|
STATIC mp_obj_t bitbangio_onewire_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *pos_args) {
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, pos_args + n_args);
enum { ARG_pin };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_pin, MP_ARG_REQUIRED | MP_ARG_OBJ },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, pos_args, &kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
assert_pin(args[ARG_pin].u_obj, false);
const mcu_pin_obj_t* pin = MP_OBJ_TO_PTR(args[ARG_pin].u_obj);
assert_pin_free(pin);
bitbangio_onewire_obj_t *self = m_new_obj(bitbangio_onewire_obj_t);
self->base.type = &bitbangio_onewire_type;
shared_module_bitbangio_onewire_construct(self, pin);
return MP_OBJ_FROM_PTR(self);
}
//| .. method:: deinit()
//|
//| Deinitialize the OneWire bus and release any hardware resources for reuse.
//|
STATIC mp_obj_t bitbangio_onewire_deinit(mp_obj_t self_in) {
bitbangio_onewire_obj_t *self = MP_OBJ_TO_PTR(self_in);
shared_module_bitbangio_onewire_deinit(self);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_onewire_deinit_obj, bitbangio_onewire_deinit);
//| .. method:: __enter__()
//|
//| No-op used by Context Managers.
//|
// Provided by context manager helper.
//| .. method:: __exit__()
//|
//| Automatically deinitializes the hardware when exiting a context. See
//| :ref:`lifetime-and-contextmanagers` for more info.
//|
STATIC mp_obj_t bitbangio_onewire_obj___exit__(size_t n_args, const mp_obj_t *args) {
(void)n_args;
shared_module_bitbangio_onewire_deinit(args[0]);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bitbangio_onewire___exit___obj, 4, 4, bitbangio_onewire_obj___exit__);
//| .. method:: reset()
//|
//| Reset the OneWire bus
//|
STATIC mp_obj_t bitbangio_onewire_obj_reset(mp_obj_t self_in) {
bitbangio_onewire_obj_t *self = MP_OBJ_TO_PTR(self_in);
return mp_obj_new_bool(shared_module_bitbangio_onewire_reset(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_onewire_reset_obj, bitbangio_onewire_obj_reset);
//| .. method:: read_bit()
//|
//| Read in a bit
//|
//| :returns: bit state read
//| :rtype: bool
//|
STATIC mp_obj_t bitbangio_onewire_obj_read_bit(mp_obj_t self_in) {
bitbangio_onewire_obj_t *self = MP_OBJ_TO_PTR(self_in);
return mp_obj_new_bool(shared_module_bitbangio_onewire_read_bit(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_onewire_read_bit_obj, bitbangio_onewire_obj_read_bit);
//| .. method:: write_bit(value)
//|
//| Write out a bit based on value.
//|
STATIC mp_obj_t bitbangio_onewire_obj_write_bit(mp_obj_t self_in, mp_obj_t bool_obj) {
bitbangio_onewire_obj_t *self = MP_OBJ_TO_PTR(self_in);
shared_module_bitbangio_onewire_write_bit(self, mp_obj_is_true(bool_obj));
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(bitbangio_onewire_write_bit_obj, bitbangio_onewire_obj_write_bit);
STATIC const mp_rom_map_elem_t bitbangio_onewire_locals_dict_table[] = {
// Methods
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&bitbangio_onewire_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&bitbangio_onewire___exit___obj) },
{ MP_ROM_QSTR(MP_QSTR_reset), MP_ROM_PTR(&bitbangio_onewire_reset_obj) },
{ MP_ROM_QSTR(MP_QSTR_read_bit), MP_ROM_PTR(&bitbangio_onewire_read_bit_obj) },
{ MP_ROM_QSTR(MP_QSTR_write_bit), MP_ROM_PTR(&bitbangio_onewire_write_bit_obj) },
};
STATIC MP_DEFINE_CONST_DICT(bitbangio_onewire_locals_dict, bitbangio_onewire_locals_dict_table);
const mp_obj_type_t bitbangio_onewire_type = {
{ &mp_type_type },
.name = MP_QSTR_OneWire,
.make_new = bitbangio_onewire_make_new,
.locals_dict = (mp_obj_dict_t*)&bitbangio_onewire_locals_dict,
};