The RH2D exposes multiple interfaces and protocol options, such as the Seed Robotics STP protocol and the well known Dynamixel Protocol.
This document assumes you are familiar with the Dynamixel Protocol.

The RH2D, like all Seed Robotics products, can be connected directly to any chain of Dynamixel devices. It is compatible with TTL and RS485 devices (depending on your choice of model) and supports the Dynamixel 1.0 and 2.0 protocol.
It will operate on the bus like any other Dynamixel device, exposing its IDs and Memory Table.

The RH2D ships configured with the following defaults:

By default the unit ships configured for operation at 1Mbps (Half Duplex UART, 8 data bits, no parity, 1 stop bit like all Dynamixel devices).

It is possible to change the communication speed from 9600bps up to 3Mbps. We recommend operating at 1Mbps.

The RH2D exposes 3 IDs on the bus:

• 1 ID for the main control board where you can query the high level functionality of the system as well as sensing, including the Palm Distance sensor and the real time current measurements (if the options is installed in your unit).
• 2 IDs for the actuators: each actuator has its own ID and Control table. Because the RH2D utilizes the Robotis XL320 servos, it exposes the XL320 control table.

IMPORTANT: Even though the Robotis XL320 operates under the Dynamixel protocol version 2, the main board performs protocol version version translation.
This means that if you have selected Dynamixel Protocol 1 in the main board (the default), you should also use Dynamixel protocol 1 to communicate with the XL320s; the main board will internally make any necessary protocol translations.

This is meant to improve compatibility and ease integration in key frameworks such as the Darwin-OP framework, by making the system operate under the same Dynamixel version.
(the Control table however, remains the same. No translation is performed here).

By default we configure the IDs of the RH2D for immediate integration into a Darwin-OP robot or a 20 servo based Robot.

• 22 Wrist Rotation
• 24 Fingers closing
• 26 Main board

• 21 Wrist Rotation
• 23 Fingers closed
• 25 Main board.

By configuring the IDs within the range <25, they are compatible with the use of Roboplus Motion and the Darwin-OP framework.
The idea is to have access to IDs 21-24 to build your motions using Roboplus Motion.

You may need to patch the Roboplus program in the Darwin-OP framework in order to have it recognize the extra IDs.
For more information, please see Operation with the Robotis Darwin OP/OP2 framework