CanBus

robodyno.interfaces.can_bus

This module provides CAN bus interface for robodyno devices.

Examples:

>>> from robodyno.interfaces import CanBus
>>> can_bus = CanBus()
>>> can_bus.send(0x10, 0x0e, 'fee', 50, 0.02, 0.1)
>>> can_bus.get(0x10, 0x0d, 'fee')
(50.0, 0.0200042724609375, 0.0999755859375)
>>> can_bus.subscribe(callback, 0x10, 0x02)
>>> can_bus.unsubscribe(callback, 0x10, 0x02)
>>> can_bus.disconnect()

CanBus

Bases: object

CAN bus interface for robodyno devices.

This class provides CAN bus interface for robodyno devices. It supports sending and receiving data from CAN bus. It also supports subscribing data from CAN bus.

A thread is created to receive data from CAN bus. When a device ID and a command ID is subscribed, the callback function will be called when the corresponding data is received.

__init__(bitrate=1000000, channel='can0', connect=True)

Initialize CAN bus interface with given channel and bitrate.

参数：

名称	类型	描述	默认
bitrate	int	CAN bus bitrate, e.g. 1000000.	1000000
channel	str	CAN bus channel name, e.g. 'can0'.	'can0'
connect	bool	Whether to connect to CAN bus.	True

引发：

类型	描述
NotImplementedError	If the platform is not supported.

connect()

Connect to CAN bus.

disconnect()

Disconnect from CAN bus.

send(device_id, cmd_id, fmt, *args)

Send data to CAN bus.

参数：

名称	类型	描述	默认
device_id	int	Device ID.	必需
cmd_id	int	Command ID.	必需
fmt	str	Format string for packing data. See struct module for details.	必需
*args		Data to be sent.	()

get(device_id, cmd_id, fmt, timeout=None)

Get data from CAN bus.

参数：

名称	类型	描述	默认
device_id	int	Device ID.	必需
cmd_id	int	Command ID.	必需
fmt	str	Format string for unpacking data. See struct module for details.	必需
timeout	float	Timeout for receiving data.	None

返回：

类型	描述
tuple	Received data.

引发：

类型	描述
TimeoutError	If timeout.

mi_motor_send(msg, timeout=None, master_id=255)

Send a CAN message and wait for the matching response from an MI motor.

参数：

名称	类型	描述	默认
msg	Message	The CAN message to send.	必需
timeout	Optional[float]	Timeout in seconds. If 0, return immediately without waiting.	None
master_id	int	Master device ID used for response filtering.	255

返回：

类型	描述
Optional[Message]	The matching response message, or None if no response is expected.

引发：

类型	描述
TimeoutError	If no response is received within the timeout.
ValueError	If the sent command is not recognized.

subscribe(callback, device_id=-1, cmd_id=-1)

Subscribe data from CAN bus.

参数：

名称	类型	描述	默认
callback	func	Callback function. The function should accept four arguments, e.g. callback(data, timestamp, device_id, cmd_id).	必需
device_id	int	Device ID. -1 for all devices.	-1
cmd_id	int	Command ID. -1 for all commands.	-1

unsubscribe(callback, device_id=-1, cmd_id=-1)

Unsubscribe data from CAN bus.

参数：

名称	类型	描述	默认
callback	func	Callback function.	必需
device_id	int	Device ID. -1 for all devices.	-1
cmd_id	int	Command ID. -1 for all commands.	-1