roboglia.dynamixel.DynamixelBus

class DynamixelBus(name='DYNAMIXEL', robot=None, port='', auto=True, baudrate=1000000, protocol=2.0, rs485=False, mock=False)

Bases: roboglia.base.bus.BaseBus

A communication bus that supports Dynamixel protocol.

Uses dynamixel_sdk.

Note

The parameters listed bellow are only the specific ones introduced by the DynamixelBus class. Since this is a subclass of BaseBus and the constructor will call the super() constructor, all the paramters supported by BaseBus are also supported and checked when creating a DynamixelBus. For instance the name, robot and port are validated.

Parameters

• name (str) – The name of the bus

• robot (BaseRobot) – A reference to the robot using the bus

• port (any) – An identification for the physical bus access. Some busses have string description like /dev/ttySC0 while others could be just integers (like in the case of I2C or SPI buses)

• auto (Bool) – If True the bus will be opened when the robot is started by calling BaseRobot.start(). If False the bus will be left closed during robot initialization and needs to be opened by the programmer.

• baudrate (int) – Communication speed for the bus

• protocol (float) – Communication protocol for the bus; must be 1.0 or 2.0

• rs485 (bool) – If True, DynamixelBus will configure the serial port with RS485 support. This might be required for certain interfaces that need this mode in order to control the semi-duplex protocol (one wire) implemented by Dynamixel devices or if you genuinely use RS485 Dynamixel devices.

• mock (bool) – Indicates to use mock bus for testing purposes; this will make use of the MockPacketHandler to simulate the communication on a Dynamixel bus and allow to test the software in CI testing.

Raises

• KeyError – if any of the required keys are missing:

• ValueError – if any of the required data is incorrect:

__init__(name='DYNAMIXEL', robot=None, port='', auto=True, baudrate=1000000, protocol=2.0, rs485=False, mock=False)

Initialize self. See help(type(self)) for accurate signature.

property port_handler

The Dynamixel port handler for this bus.

property packet_handler

The Dynamixel packet handler for this bus.

property protocol

Protocol supported by the bus.

property baudrate

Bus baudrate.

property rs485

If the bus uses rs485.

open()

Allocates the port_handler and the packet_handler. If the attribute mock was True when setting up the bus, then uses MockPacketHandler.

close()

Closes the actual physical bus. Calls the super().close() to check if there is ok to close the bus and no other objects are using it.

property is_open

Returns True or False if the bus is open.

ping(dxl_id)

Performs a Dynamixel ping of a device.

Parameters

dxl_id (int) – The Dynamixel device number to be pinged.

Returns

True if the device responded, False otherwise.

Return type

bool

scan(range=[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253])

Scans the devices on the bus.

Parameters

• range (range) – the range of devices to be cheked if they exist on the bus. The method will call ping() for each ID in the list. By default the list is [0, 253].

• Returns –

• of int (list) – The list of IDs that have been successfully identified on the bus. If none is found the list will be empty.

read(reg)

Depending on the size of the register calls the corresponding TxRx function from the packet handler. If the result is ok (communication error and dynamixel error are both 0) then the obtained value is returned. Communication and data errors are logged and no exceptions are raised.

Parameters

reg (BaseRegister or subclass) – The register to be read

Returns

The value read by calling the device.

Return type

int

write(reg, value)

Depending on the size of the register calls the corresponding TxRx function from the packet handler. Communication and data errors are logged and no exceptions are raised.

Parameters

• reg (BaseRegister or subclass) – The register to write to

• value (int) – The value to write to the register. Please note that this is in the internal format of the register and it is the responsibility of the register class to provide conversion between the internal and external format if they are different.

__repr__()

Returns a representation of a BaseBus that includes the name of the class, the port and the status (open or closed).

property auto_open

Indicates if the bus should be opened by the robot when initializing.

property name

(read-only) the bus name.

property port

(read-only) the bus port.

property robot

The robot that owns the bus.