Dynamixel AX-12A Robot Actuator

Datasheet

AX-12A Datasheet

Installing the library

  • Download zip file
  • Extract zip
  • Rename the folder : AX-12A-servo-library-master --> AX-12A-servo-library
  • Put the folder into your library folder (usually Documents/Arduino/libraries)

Using the library

To use the library, include header file located in the src folder.

#include "AX12A.h"

The library is provided with 4 Arduino examples :

  • Blink : simpliest example to blink the built-in LED
  • Move : example showing how to set a goal position
  • EndlessTurn : example of endlessTurn mode (wheel mode)
  • readRegister : debug AX-12A by printing all its registers

You have 4 lines to configure :

#define DirectionPin  (10u)
#define BaudRate      (1000000ul)
#define ID            (1u)
...
AX12A.begin(BaudRate, DirectionPin, &Serial);

DirectionPin is the GPIO used to change communication direction.

BaudRate corresponds to the baud rate used to communicate with the servo.

ID corresponds to the ID of the servo (from 0 to 253, 254 is used for broadcast).

&Serial refers to the serial port you want to use. It may have to be changed to &Serial1, &SerialUSB or other depending on the board package you use (variant files).

Change AX-12A settings by connecting the servo to a PC via USB2Dynamixel.

To do so, install Dynamixel Wizard included in the RoboPlus software suite.

Follow these instructions to connect and access the AX-12A settings.

Baud rate tests

We tested the library on differents boards at the most common baud rates.

Some boards cannot reach the desired baud rate :

Address 0x04 Baud rate Feather M0 Feather 32u4 nRF52 STM32L4
1 1000000 ok ok ok fail
3 500000 ok ok fail ok
4 400000 ok fail fail ok
7 250000 ok ok ok ok
9 200000 ok ok fail ok
16 115200 ok ok ok ok
34 57600 ok fail ok ok
103 19200 ok ok ok ok
207 9600 ok ok ok ok