circuitpython/shared-bindings/_canio/Message.c
Jeff Epler a2e1867f69 _canio: Minimal implementation for SAM E5x MCUs
Tested & working:

 * Send standard packets
 * Receive standard packets (1 FIFO, no filter)

Interoperation between SAM E54 Xplained running this tree and
MicroPython running on STM32F405 Feather with an external
transceiver was also tested.

Many other aspects of a full implementation are not yet present,
such as error detection and recovery.
2020-09-21 16:44:26 -05:00

214 lines
8.2 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2020 Jeff Epler 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 "shared-bindings/_canio/Message.h"
#include "shared-module/_canio/Message.h"
#include "py/obj.h"
#include "py/objproperty.h"
#include "py/runtime.h"
//| class Message:
//| def __init__(self, id: int=0, data: Optional[bytes] = None, *, size: Optional[int] = None, rtr: bool = False):
//| """Construct a Message to send on a CAN bus
//|
//| :param int id: The numeric ID of the message
//| :param bytes data: The content of the message
//| :param int size: The amount of data requested, for an rtr
//| :param bool rtr: True if the message represents an rtr (Remote Transmission Request)
//|
//| In CAN, messages can have a size from 0 to 8 bytes.
//|
//| For a non-rtr message, specify `data`. For an rtr-message, specify either `data` (a dummy buffer of the requested size) or `size`.
//| """
//| ...
//|
STATIC mp_obj_t canio_message_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_id, ARG_data, ARG_size, ARG_rtr, NUM_ARGS };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_id, MP_ARG_INT, {.u_obj = 0} },
{ MP_QSTR_data, MP_ARG_OBJ, {.u_obj = 0} },
{ MP_QSTR_size, MP_ARG_INT, {.u_int = -1} },
{ MP_QSTR_rtr, MP_ARG_BOOL, {.u_bool = false} },
};
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
MP_STATIC_ASSERT( MP_ARRAY_SIZE(allowed_args) == NUM_ARGS );
mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
bool rtr = args[ARG_rtr].u_bool;
size_t size = (size_t)args[ARG_size].u_int;
bool specified_size = (size != (size_t)-1);
bool specified_data = (args[ARG_data].u_obj != NULL);
if(specified_size && specified_data) {
mp_raise_TypeError(translate("specify size or data, but not both"));
}
mp_buffer_info_t data;
if (specified_data) {
mp_get_buffer_raise(args[ARG_data].u_obj, &data, MP_BUFFER_READ);
} else if (specified_size) {
data.buf = 0;
data.len = size;
} else {
data.buf = 0;
data.len = 0;
}
if(data.len > 8) {
mp_raise_ValueError(translate("Messages limited to 8 bytes"));
}
canio_message_obj_t *self = m_new_obj(canio_message_obj_t);
self->base.type = &canio_message_type;
common_hal_canio_message_construct(self, args[ARG_id].u_int, data.buf, data.len, rtr);
return self;
}
//| id: int
//| """The numeric ID of the message"""
//|
STATIC mp_obj_t canio_message_id_get(const mp_obj_t self_in) {
canio_message_obj_t *self = self_in;
return MP_OBJ_NEW_SMALL_INT(common_hal_canio_message_id_get(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(canio_message_id_get_obj, canio_message_id_get);
STATIC mp_obj_t canio_message_id_set(const mp_obj_t self_in, const mp_obj_t id) {
canio_message_obj_t *self = self_in;
common_hal_canio_message_id_set(self, mp_obj_get_int(id));
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(canio_message_id_set_obj, canio_message_id_set);
STATIC const mp_obj_property_t canio_message_id_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&canio_message_id_get_obj,
(mp_obj_t)&canio_message_id_set_obj,
(mp_obj_t)&mp_const_none_obj},
};
//| data: bytes
//| """The content of the message, or dummy content in the case of an rtr.
//|
//| Assigning to data sets the bytes to zero"""
//|
STATIC mp_obj_t canio_message_data_get(const mp_obj_t self_in) {
canio_message_obj_t *self = self_in;
return mp_obj_new_bytes((const byte*)common_hal_canio_message_data_get(self), common_hal_canio_message_size_get(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(canio_message_data_get_obj, canio_message_data_get);
STATIC mp_obj_t canio_message_data_set(const mp_obj_t self_in, const mp_obj_t data_in) {
canio_message_obj_t *self = self_in;
mp_buffer_info_t data;
mp_get_buffer_raise(data_in, &data, MP_BUFFER_READ);
if(data.len > 8) {
mp_raise_ValueError(translate("Messages limited to 8 bytes"));
}
common_hal_canio_message_data_set(self, data.buf, data.len);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(canio_message_data_set_obj, canio_message_data_set);
STATIC const mp_obj_property_t canio_message_data_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&canio_message_data_get_obj,
(mp_obj_t)&canio_message_data_set_obj,
(mp_obj_t)&mp_const_none_obj},
};
//| size: int
//| """The length of the message, or the length of the requested data in the case of an rtr"""
//|
STATIC mp_obj_t canio_message_size_get(const mp_obj_t self_in) {
canio_message_obj_t *self = self_in;
return MP_OBJ_NEW_SMALL_INT(common_hal_canio_message_size_get(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(canio_message_size_get_obj, canio_message_size_get);
STATIC mp_obj_t canio_message_size_set(const mp_obj_t self_in, const mp_obj_t size_in) {
canio_message_obj_t *self = self_in;
int size = mp_obj_get_int(size_in);
if(size > 8) {
mp_raise_ValueError(translate("Messages limited to 8 bytes"));
}
common_hal_canio_message_size_set(self, size);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(canio_message_size_set_obj, canio_message_size_set);
STATIC const mp_obj_property_t canio_message_size_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&canio_message_size_get_obj,
(mp_obj_t)&canio_message_size_set_obj,
(mp_obj_t)&mp_const_none_obj},
};
//| rtr: bool
//| """True if the message represents a remote transmission request (RTR)"""
//|
STATIC mp_obj_t canio_message_rtr_get(const mp_obj_t self_in) {
canio_message_obj_t *self = self_in;
return mp_obj_new_bool(common_hal_canio_message_rtr_get(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(canio_message_rtr_get_obj, canio_message_rtr_get);
STATIC mp_obj_t canio_message_rtr_set(const mp_obj_t self_in, const mp_obj_t rtr) {
canio_message_obj_t *self = self_in;
common_hal_canio_message_size_set(self, mp_obj_is_true(rtr));
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(canio_message_rtr_set_obj, canio_message_rtr_set);
STATIC const mp_obj_property_t canio_message_rtr_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&canio_message_rtr_get_obj,
(mp_obj_t)&canio_message_rtr_set_obj,
(mp_obj_t)&mp_const_none_obj},
};
STATIC const mp_rom_map_elem_t canio_message_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_id), MP_ROM_PTR(&canio_message_id_obj) },
{ MP_ROM_QSTR(MP_QSTR_data), MP_ROM_PTR(&canio_message_data_obj) },
{ MP_ROM_QSTR(MP_QSTR_size), MP_ROM_PTR(&canio_message_size_obj) },
{ MP_ROM_QSTR(MP_QSTR_rtr), MP_ROM_PTR(&canio_message_rtr_obj) },
};
STATIC MP_DEFINE_CONST_DICT(canio_message_locals_dict, canio_message_locals_dict_table);
const mp_obj_type_t canio_message_type = {
{ &mp_type_type },
.name = MP_QSTR_Message,
.make_new = canio_message_make_new,
.locals_dict = (mp_obj_t)&canio_message_locals_dict,
};