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circuitpython/shared-bindings/nativeio/UART.c

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/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 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 "shared-bindings/nativeio/UART.h"
#include "lib/utils/context_manager_helpers.h"
#include "py/ioctl.h"
#include "py/runtime.h"
#include "py/stream.h"
#include "shared-bindings/microcontroller/Pin.h"
//| .. currentmodule:: nativeio
//|
//| :class:`UART` -- a bidirectional serial protocol
//| =================================================
//|
//|
//| .. class:: UART(tx, rx, \*, baudrate=9600, bits=8, parity=None, stop=1, timeout=1000, receiver_buffer_size=64)
//|
//| A common bidirectional serial protocol that uses an an agreed upon speed
//| rather than a shared clock line.
//|
//| :param ~microcontroller.Pin tx: the pin to transmit with
//| :param ~microcontroller.Pin rx: the pin to receive on
//| :param int baudrate: the transmit and receive speed
/// :param int bits: the number of bits per byte, 7, 8 or 9.
/// :param Parity parity: the parity used for error checking
/// :param int stop: the number of stop bits, 1 or 2.
/// :param int timeout: the timeout in milliseconds to wait for the first character and between subsequent characters.
/// :param int receiver_buffer_size: the character length of the read buffer (0 to disable). (When a character is 9 bits the buffer will be 2 * receiver_buffer_size bytes.)
//|
typedef struct {
mp_obj_base_t base;
} nativeio_uart_parity_obj_t;
extern const nativeio_uart_parity_obj_t nativeio_uart_parity_even_obj;
extern const nativeio_uart_parity_obj_t nativeio_uart_parity_odd_obj;
STATIC mp_obj_t nativeio_uart_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, 0, MP_OBJ_FUN_ARGS_MAX, true);
nativeio_uart_obj_t *self = m_new_obj(nativeio_uart_obj_t);
self->base.type = &nativeio_uart_type;
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, pos_args + n_args);
enum { ARG_tx, ARG_rx, ARG_baudrate, ARG_bits, ARG_parity, ARG_stop, ARG_timeout, ARG_receiver_buffer_size};
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_tx, MP_ARG_REQUIRED | MP_ARG_OBJ },
{ MP_QSTR_rx, MP_ARG_REQUIRED | MP_ARG_OBJ },
{ MP_QSTR_baudrate, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 9600} },
{ MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} },
{ MP_QSTR_parity, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
{ MP_QSTR_stop, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1} },
{ MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1000} },
{ MP_QSTR_receiver_buffer_size, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 64} },
};
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_rx].u_obj, true);
const mcu_pin_obj_t* rx = MP_OBJ_TO_PTR(args[ARG_rx].u_obj);
assert_pin_free(rx);
assert_pin(args[ARG_tx].u_obj, true);
const mcu_pin_obj_t* tx = MP_OBJ_TO_PTR(args[ARG_tx].u_obj);
assert_pin_free(tx);
uint8_t bits = args[ARG_bits].u_int;
if (bits < 7 || bits > 9) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError,
"bits must be 7, 8 or 9"));
}
uart_parity_t parity = PARITY_NONE;
if (args[ARG_parity].u_obj == &nativeio_uart_parity_even_obj) {
parity = PARITY_EVEN;
} else if (args[ARG_parity].u_obj == &nativeio_uart_parity_odd_obj) {
parity = PARITY_ODD;
}
uint8_t stop = args[ARG_stop].u_int;
if (stop != 1 && stop != 2) {
nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError,
"stop must be 1 or 2"));
}
common_hal_nativeio_uart_construct(self, tx, rx,
args[ARG_baudrate].u_int, bits, parity, stop, args[ARG_timeout].u_int,
args[ARG_receiver_buffer_size].u_int);
return (mp_obj_t)self;
}
//| .. method:: deinit()
//|
//| Deinitialises the UART and releases any hardware resources for reuse.
//|
STATIC mp_obj_t nativeio_uart_obj_deinit(mp_obj_t self_in) {
nativeio_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
common_hal_nativeio_uart_deinit(self);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(nativeio_uart_deinit_obj, nativeio_uart_obj_deinit);
//| .. method:: __enter__()
//|
//| No-op used by Context Managers.
//|
// Provided by context manager helper.
//| .. method:: __exit__()
//|
//| Automatically deinitializes the hardware when exiting a context.
//|
STATIC mp_obj_t nativeio_uart_obj___exit__(size_t n_args, const mp_obj_t *args) {
(void)n_args;
common_hal_nativeio_uart_deinit(args[0]);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(nativeio_uart___exit___obj, 4, 4, nativeio_uart_obj___exit__);
// These are standard stream methods. Code is in py/stream.c.
//
//| .. method:: read([nbytes])
//|
//| Read characters. If ``nbytes`` is specified then read at most that many
//| bytes. Otherwise, read everything that has been buffered.
//|
//| :return: Data read
//| :rtype: bytes or None
//|
//| .. method:: readinto(buf[, nbytes])
//|
//| Read bytes into the ``buf``. If ``nbytes`` is specified then read at most
//| that many bytes. Otherwise, read at most ``len(buf)`` bytes.
//|
//| :return: number of bytes read and stored into ``buf``
//| :rtype: bytes or None
//|
//| .. method:: readline()
//|
//| Read a line, ending in a newline character.
//|
//| :return: the line read
//| :rtype: int or None
//|
//| .. method:: write(buf)
//|
//| Write the buffer of bytes to the bus.
//|
//| :return: the number of bytes written
//| :rtype: int or None
//|
// These three methods are used by the shared stream methods.
STATIC mp_uint_t nativeio_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t size, int *errcode) {
nativeio_uart_obj_t *self = self_in;
byte *buf = buf_in;
// make sure we want at least 1 char
if (size == 0) {
return 0;
}
return common_hal_nativeio_uart_read(self, buf, size, errcode);
}
STATIC mp_uint_t nativeio_uart_write(mp_obj_t self_in, const void *buf_in, mp_uint_t size, int *errcode) {
nativeio_uart_obj_t *self = self_in;
const byte *buf = buf_in;
return common_hal_nativeio_uart_write(self, buf, size, errcode);
}
STATIC mp_uint_t nativeio_uart_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint_t arg, int *errcode) {
nativeio_uart_obj_t *self = self_in;
mp_uint_t ret;
if (request == MP_IOCTL_POLL) {
mp_uint_t flags = arg;
ret = 0;
if ((flags & MP_IOCTL_POLL_RD) && common_hal_nativeio_uart_rx_characters_available(self) > 0) {
ret |= MP_IOCTL_POLL_RD;
}
if ((flags & MP_IOCTL_POLL_WR) && common_hal_nativeio_uart_ready_to_tx(self)) {
ret |= MP_IOCTL_POLL_WR;
}
} else {
*errcode = MP_EINVAL;
ret = MP_STREAM_ERROR;
}
return ret;
}
//| .. class:: nativeio.UART.Parity
//|
//| Enum-like class to define the parity used to verify correct data transfer.
//|
//| .. data:: ODD
//|
//| Total number of ones should be odd.
//|
//| .. data:: EVEN
//|
//| Total number of ones should be even.
//|
const mp_obj_type_t nativeio_uart_parity_type;
const nativeio_uart_parity_obj_t nativeio_uart_parity_odd_obj = {
{ &nativeio_uart_parity_type },
};
const nativeio_uart_parity_obj_t nativeio_uart_parity_even_obj = {
{ &nativeio_uart_parity_type },
};
STATIC const mp_rom_map_elem_t nativeio_uart_parity_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_ODD), MP_ROM_PTR(&nativeio_uart_parity_odd_obj) },
{ MP_ROM_QSTR(MP_QSTR_EVEN), MP_ROM_PTR(&nativeio_uart_parity_even_obj) },
};
STATIC MP_DEFINE_CONST_DICT(nativeio_uart_parity_locals_dict, nativeio_uart_parity_locals_dict_table);
STATIC void nativeio_uart_parity_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
qstr parity = MP_QSTR_ODD;
if (MP_OBJ_TO_PTR(self_in) == MP_ROM_PTR(&nativeio_uart_parity_even_obj)) {
parity = MP_QSTR_EVEN;
}
mp_printf(print, "%q.%q.%q.%q", MP_QSTR_nativeio, MP_QSTR_UART, MP_QSTR_Parity, parity);
}
const mp_obj_type_t nativeio_uart_parity_type = {
{ &mp_type_type },
.name = MP_QSTR_Parity,
.print = nativeio_uart_parity_print,
.locals_dict = (mp_obj_t)&nativeio_uart_parity_locals_dict,
};
STATIC const mp_rom_map_elem_t nativeio_uart_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&nativeio_uart_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&nativeio_uart___exit___obj) },
// Standard stream methods.
{ MP_OBJ_NEW_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj)},
{ MP_OBJ_NEW_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
// Nested Enum-like Classes.
{ MP_ROM_QSTR(MP_QSTR_Parity), MP_ROM_PTR(&nativeio_uart_parity_type) },
};
STATIC MP_DEFINE_CONST_DICT(nativeio_uart_locals_dict, nativeio_uart_locals_dict_table);
STATIC const mp_stream_p_t uart_stream_p = {
.read = nativeio_uart_read,
.write = nativeio_uart_write,
.ioctl = nativeio_uart_ioctl,
.is_text = false,
};
const mp_obj_type_t nativeio_uart_type = {
{ &mp_type_type },
.name = MP_QSTR_UART,
.make_new = nativeio_uart_make_new,
.getiter = mp_identity,
.iternext = mp_stream_unbuffered_iter,
.protocol = &uart_stream_p,
.locals_dict = (mp_obj_dict_t*)&nativeio_uart_locals_dict,
};