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Matlab Indirect Address Protocol 2.0

Sample code

%
% indirect_address.m
%
%  Created on: 2016. 6. 7.
%      Author: Ryu Woon Jung (Leon)
%

%
% *********     Indirect Address Example      *********
%
%
% Available Dynamixel model on this example : All models using Protocol 2.0
% This example is designed for using a Dynamixel PRO 54-200, and an USB2DYNAMIXEL.
% To use another Dynamixel model, such as X series, see their details in E-Manual(support.robotis.com) and edit below variables yourself.
% Be sure that Dynamixel PRO properties are already set as %% ID : 1 / Baudnum : 3 (Baudrate : 1000000 [1M])
%

clc;
clear all;

% Load Libraries
if ~libisloaded('dxl_x86_c');
    [notfound, warnings] = loadlibrary('dxl_x86_c', 'dynamixel_sdk.h', 'addheader', 'port_handler.h', 'addheader', 'packet_handler.h', 'addheader', 'group_sync_write.h', 'addheader', 'group_sync_read.h');
end

% Control table address                                            % Control table address is different in Dynamixel model
ADDR_PRO_INDIRECTADDRESS_FOR_WRITE      = 49;                  % EEPROM region
ADDR_PRO_INDIRECTADDRESS_FOR_READ       = 59;                  % EEPROM region
ADDR_PRO_TORQUE_ENABLE                  = 562;
ADDR_PRO_LED_RED                        = 563;
ADDR_PRO_GOAL_POSITION                  = 596;
ADDR_PRO_MOVING                         = 610;
ADDR_PRO_PRESENT_POSITION               = 611;
ADDR_PRO_INDIRECTDATA_FOR_WRITE         = 634;
ADDR_PRO_INDIRECTDATA_FOR_READ          = 639;

% Data Byte Length
LEN_PRO_LED_RED                         = 1;
LEN_PRO_GOAL_POSITION                   = 4;
LEN_PRO_MOVING                          = 1;
LEN_PRO_PRESENT_POSITION                = 4;
LEN_PRO_INDIRECTDATA_FOR_WRITE          = 5;
LEN_PRO_INDIRECTDATA_FOR_READ           = 5;

% Protocol version
PROTOCOL_VERSION                        = 2.0;                % See which protocol version is used in the Dynamixel

% Default setting
DXL_ID                                  = 1;                  % Dynamixel ID: 1
BAUDRATE                                = 1000000;
DEVICENAME                              = 'COM1';             % Check which port is being used on your controller
                                                              % ex) Windows: "COM1"   Linux: "/dev/ttyUSB0"

TORQUE_ENABLE                           = 1;                  % Value for enabling the torque
TORQUE_DISABLE                          = 0;                  % Value for disabling the torque
DXL_MINIMUM_POSITION_VALUE              = -150000;            % Dynamixel will rotate between this value
DXL_MAXIMUM_POSITION_VALUE              = 150000;             % and this value (note that the Dynamixel would not move when the position value is out of movable range. Check e-manual about the range of the Dynamixel you use.)
DXL_MINIMUM_LED_VALUE                   = 0;                  % Dynamixel LED will light between this value
DXL_MAXIMUM_LED_VALUE                   = 255;                % and this value
DXL_MOVING_STATUS_THRESHOLD             = 20;                 % Dynamixel moving status threshold

ESC_CHARACTER                           = 'e';                % Key for escaping loop

COMM_SUCCESS                            = 0;                  % Communication Success result value
COMM_TX_FAIL                            = -1001;              % Communication Tx Failed

% Initialize PortHandler Structs
% Set the port path
% Get methods and members of PortHandlerLinux or PortHandlerWindows
port_num = portHandler(DEVICENAME);

% Initialize PacketHandler Structs
packetHandler();

% Initialize Groupsyncwrite Structs
groupwrite_num = groupSyncWrite(port_num, PROTOCOL_VERSION, ADDR_PRO_INDIRECTDATA_FOR_WRITE, LEN_PRO_INDIRECTDATA_FOR_WRITE);

% Initialize Groupsyncread Structs for Present Position
groupread_num = groupSyncRead(port_num, PROTOCOL_VERSION, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_INDIRECTDATA_FOR_READ);

index = 1;
dxl_comm_result = COMM_TX_FAIL;                               % Communication result
dxl_addparam_result = false;                                  % AddParam result
dxl_getdata_result = false;                                   % GetParam result
dxl_goal_position = [DXL_MINIMUM_POSITION_VALUE DXL_MAXIMUM_POSITION_VALUE];         % Goal position

dxl_error = 0;                                                % Dynamixel error
dxl_moving = 0;                                               % Dynamixel moving status
dxl_led_value = [0 255];                                      % Dynamixel LED value
dxl_present_position = 0;                                     % Present position


% Open port
if (openPort(port_num))
    fprintf('Succeeded to open the port!\n');
else
    unloadlibrary('dxl_x86_c');
    fprintf('Failed to open the port!\n');
    input('Press any key to terminate...\n');
    return;
end


% Set port baudrate
if (setBaudRate(port_num, BAUDRATE))
    fprintf('Succeeded to change the baudrate!\n');
else
    unloadlibrary('dxl_x86_c');
    fprintf('Failed to change the baudrate!\n');
    input('Press any key to terminate...\n');
    return;
end


% Disable Dynamixel Torque :
% Indirect address would not accessible when the torque is already enabled
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_DISABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
else
    fprintf('Dynamixel has been successfully connected \n');
end

% INDIRECTDATA parameter storages replace LED, goal position, present position and moving status storages
write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 0, ADDR_PRO_GOAL_POSITION + 0);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 2, ADDR_PRO_GOAL_POSITION + 1);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 4, ADDR_PRO_GOAL_POSITION + 2);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 6, ADDR_PRO_GOAL_POSITION + 3);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 8, ADDR_PRO_LED_RED);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 0, ADDR_PRO_PRESENT_POSITION + 0);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 2, ADDR_PRO_PRESENT_POSITION + 1);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 4, ADDR_PRO_PRESENT_POSITION + 2);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 6, ADDR_PRO_PRESENT_POSITION + 3);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 8, ADDR_PRO_MOVING);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

% Enable Dynamixel Torque
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_ENABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

% Add parameter storage for the present position value
dxl_addparam_result = groupSyncReadAddParam(groupread_num, DXL_ID);
if dxl_addparam_result ~= true
  fprintf('[ID:%03d] groupSyncRead addparam failed', DXL1_ID);
  return;
end


while 1
    if input('Press any key to continue! (or input e to quit!)\n', 's') == ESC_CHARACTER
        break;
    end

    % Add values to the Syncwrite storage
    dxl_addparam_result = groupSyncWriteAddParam(groupwrite_num, DXL_ID, typecast(int32(dxl_goal_position(index)), 'uint32'), LEN_PRO_GOAL_POSITION);
    if dxl_addparam_result ~= true
        fprintf('[ID:%03d] groupSyncWrite addparam failed', DXL1_ID);
        return;
    end
    dxl_addparam_result = groupSyncWriteAddParam(groupwrite_num, DXL_ID, dxl_led_value(index), LEN_PRO_LED_RED);
    if dxl_addparam_result ~= true
        fprintf('[ID:%03d] groupSyncWrite addparam failed', DXL1_ID);
        return;
    end

    % Syncwrite all
    groupSyncWriteTxPacket(groupwrite_num);
    if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
        printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
    end

    % Clear syncwrite parameter storage
    groupSyncWriteClearParam(groupwrite_num);

    while 1
      % Syncread present position from indirectdata2
      groupSyncReadTxRxPacket(groupread_num);
      if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
          printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
      end

      % Check if groupsyncread data of Dyanamixel is available
      dxl_getdata_result = groupSyncReadIsAvailable(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_PRESENT_POSITION);
      if dxl_getdata_result ~= true
        fprintf('[ID:%03d] groupSyncRead getdata failed', DXL1_ID);
        return;
      end

      % Check if groupsyncread data of Dyanamixel is available
      dxl_getdata_result = groupSyncReadIsAvailable(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ + LEN_PRO_PRESENT_POSITION, LEN_PRO_MOVING);
      if dxl_getdata_result ~= true
        fprintf('[ID:%03d] groupSyncRead getdata failed', DXL1_ID);
        return;
      end

      % Get Dynamixel present position value
      dxl_present_position = groupSyncReadGetData(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_PRESENT_POSITION);

      % Get Dynamixel moving status value
      dxl_moving = groupSyncReadGetData(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ + LEN_PRO_PRESENT_POSITION, LEN_PRO_MOVING);

      fprintf('[ID:%03d] GoalPos:%d  PresPos:%d  IsMoving:%d\n', DXL_ID, dxl_goal_position(index), typecast(uint32(dxl_present_position), 'int32'), dxl_moving);

      if ~(abs(dxl_goal_position(index) - typecast(uint32(dxl_present_position), 'int32')) > DXL_MOVING_STATUS_THRESHOLD)
        break;
      end
    end

    % Change goal position
    if index == 1
        index = 2;
    else
        index = 1;
    end
end


% Disable Dynamixel Torque
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_DISABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

% Close port
closePort(port_num);

% Unload Library
unloadlibrary('dxl_x86_c');

close all;
clear all;

Details

% Load Libraries
if ~libisloaded('dxl_x86_c');
    [notfound, warnings] = loadlibrary('dxl_x86_c', 'dynamixel_sdk.h', 'addheader', 'port_handler.h', 'addheader', 'packet_handler.h', 'addheader', 'group_sync_write.h', 'addheader', 'group_sync_read.h');
end

This example uses dynamixel library imported by loadlibrary().

% Control table address                                            % Control table address is different in Dynamixel model
ADDR_PRO_INDIRECTADDRESS_FOR_WRITE      = 49;                  % EEPROM region
ADDR_PRO_INDIRECTADDRESS_FOR_READ       = 59;                  % EEPROM region
ADDR_PRO_TORQUE_ENABLE                  = 562;
ADDR_PRO_LED_RED                        = 563;
ADDR_PRO_GOAL_POSITION                  = 596;
ADDR_PRO_MOVING                         = 610;
ADDR_PRO_PRESENT_POSITION               = 611;
ADDR_PRO_INDIRECTDATA_FOR_WRITE         = 634;
ADDR_PRO_INDIRECTDATA_FOR_READ          = 639;

% Data Byte Length
LEN_PRO_LED_RED                         = 1;
LEN_PRO_GOAL_POSITION                   = 4;
LEN_PRO_MOVING                          = 1;
LEN_PRO_PRESENT_POSITION                = 4;
LEN_PRO_INDIRECTDATA_FOR_WRITE          = 5;
LEN_PRO_INDIRECTDATA_FOR_READ           = 5;

Dynamixel series have their own control tables: Addresses and Byte Length in each items. To control one of the items, its address (and length if necessary) is required. Find your requirements in http://emanual.robotis.com/.

% Protocol version
PROTOCOL_VERSION                        = 2.0;                % See which protocol version is used in the Dynamixel

Dynamixel uses either or both protocols: Protocol 1.0 and Protocol 2.0. Choose one of the Protocol which is appropriate in the Dynamixel.

% Default setting
DXL_ID                                  = 1;                  % Dynamixel ID: 1
BAUDRATE                                = 1000000;
DEVICENAME                              = 'COM1';             % Check which port is being used on your controller
                                                              % ex) Windows: "COM1"   Linux: "/dev/ttyUSB0"

TORQUE_ENABLE                           = 1;                  % Value for enabling the torque
TORQUE_DISABLE                          = 0;                  % Value for disabling the torque
DXL_MINIMUM_POSITION_VALUE              = -150000;            % Dynamixel will rotate between this value
DXL_MAXIMUM_POSITION_VALUE              = 150000;             % and this value (note that the Dynamixel would not move when the position value is out of movable range. Check e-manual about the range of the Dynamixel you use.)
DXL_MINIMUM_LED_VALUE                   = 0;                  % Dynamixel LED will light between this value
DXL_MAXIMUM_LED_VALUE                   = 255;                % and this value
DXL_MOVING_STATUS_THRESHOLD             = 20;                 % Dynamixel moving status threshold

ESC_CHARACTER                           = 'e';                % Key for escaping loop

Here we set some variables to let you freely change them and use them to run the example code.

As the document previously said in previous chapter, customize Dynamixel control table items, such as DXL_ID number, communication BAUDRATE, and the DEVICENAME, on your own terms of needs. In particular, BAUDRATE and DEVICENAME have systematical dependencies on your controller, so make clear what kind of communication method you will use.

The example uses Dynamixel DXL_ID connected with the port DEVICENAME.

Dynamixel basically needs the TORQUE_ENABLE to be rotating or give you its internal information. On the other hand, it doesn’t need torque enabled if you get your goal, so finally do TORQUE_DISABLE to prepare to the next sequence.

Since the Dynamixel has its own rotation range, it may shows malfunction if your request on your dynamixel is out of range. For example, Dynamixel MX-28 and Dynamixel PRO 54-200 has its rotatable range as 0 ~ 4028 and -250950 ~ 250950, each.

Dynamixel LED has its own range of value: 1 byte red LED for Dynamixel MX-28 and 1byte each on red, green, blue LED for Dynamixel PRO 54-200.

DXL_MOVING_STATUS_THRESHOLD acts as a criteria for verifying its rotation stopped.

COMM_SUCCESS                            = 0;                  % Communication Success result value
COMM_TX_FAIL                            = -1001;              % Communication Tx Failed

Each of the variables above show the meaning of the communication result value.

% Initialize PortHandler Structs
% Set the port path
% Get methods and members of PortHandlerLinux or PortHandlerWindows
port_num = portHandler(DEVICENAME);

portHandler() function sets port path as DEVICENAME and get port_num, and prepares an appropriate functions for port control in controller OS automatically. port_num would be used in many functions in the body of the code to specify the port for use.

% Initialize PacketHandler Structs
packetHandler();

packetHandler() function initializes parameters used for packet construction and packet storing.

% Initialize Groupsyncwrite Structs
groupwrite_num = groupSyncWrite(port_num, PROTOCOL_VERSION, ADDR_PRO_INDIRECTDATA_FOR_WRITE, LEN_PRO_INDIRECTDATA_FOR_WRITE);

groupSyncWrite() function initializes grouped parameters used for packet construction and packet storing. The utility functions of sync write deals simultaneously with more than one Dynamixel through #port_num port, building packets by the function which uses PROTOCOL_VERSION, and writing LEN_PRO_INDIRECTDATA_FOR_WRITE bytes of the values on the address ADDR_PRO_INDIRECTDATA_FOR_WRITE.

% Initialize Groupsyncread Structs for Present Position
groupread_num = groupSyncRead(port_num, PROTOCOL_VERSION, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_INDIRECTDATA_FOR_READ);

groupSyncRead() function initializes grouped parameters used for packet construction and packet storing. The utility functions of sync read deals simultaneously with more than one Dynamixel through #port_num port, building packets by the function which uses PROTOCOL_VERSION, and requesting LEN_PRO_INDIRECTDATA_FOR_READ bytes of the values on the address ADDR_PRO_INDIRECTDATA_FOR_READ.

index = 1;
dxl_comm_result = COMM_TX_FAIL;                               % Communication result
dxl_addparam_result = false;                                  % AddParam result
dxl_getdata_result = false;                                   % GetParam result
dxl_goal_position = [DXL_MINIMUM_POSITION_VALUE DXL_MAXIMUM_POSITION_VALUE];         % Goal position

dxl_error = 0;                                                % Dynamixel error
dxl_moving = 0;                                               % Dynamixel moving status
dxl_led_value = [0 255];                                      % Dynamixel LED value
dxl_present_position = 0;                                     % Present position

index variable points the direction to where the Dynamixel should be rotated.

dxl_comm_result indicates which error has been occurred during packet communication.

dxl_addparam_result indicates the result of parameter addition used for sync/bulk related functions

dxl_getdata_result indicates the result of data reception used for sync/bulk related functions

dxl_goal_position stores goal points of Dynamixel rotation.

dxl_error shows the internal error in Dynamixel.

dxl_moving views whether the Dynamixel is stopped.

dxl_led_value stores LED values of Dynamixel.

dxl_present_position view where now each Dynamixel points out.

% Open port
if (openPort(port_num))
    fprintf('Succeeded to open the port!\n');
else
    unloadlibrary('dxl_x86_c');
    fprintf('Failed to open the port!\n');
    input('Press any key to terminate...\n');
    return;
end

First, controller opens #port_num port to do serial communication with the Dynamixel. If it fails to open the port, the example will be terminated.

% Set port baudrate
if (setBaudRate(port_num, BAUDRATE))
    fprintf('Succeeded to change the baudrate!\n');
else
    unloadlibrary('dxl_x86_c');
    fprintf('Failed to change the baudrate!\n');
    input('Press any key to terminate...\n');
    return;
end

Secondly, the controller sets the communication BAUDRATE at #port_num port opened previously.

% Disable Dynamixel Torque :
% Indirect address would not accessible when the torque is already enabled
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_DISABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
else
    fprintf('Dynamixel has been successfully connected \n');
end

Indirect address and Indirect data are particularly applicable to control several items far from each other in control table address simultaenously. Nth Indirect data shows one of the item on the control table that Nth Indirect Address points out, so if you want to see Dynamixel LED RED value through 1st indirect data, change value of 1st Indirect Address to ADDR_PRO_LED_RED value.

However, Dynamixel PRO has Indirect Address items on its EEPROM area. (Please see the E-Manual.) To change them, you must disable the torque at first.

Above write1ByteTxRx() function orders to the #DXL_ID Dynamixel through the port, writing 1 byte of TORQUE_DISABLE value to ADDR_PRO_TORQUE_ENABLE address. The function checks Tx/Rx result and receives Hardware error. getLastTxRxResult() function and getLastRxPacketError() function get either, and then printTxRxResult() function and printRxPacketError() function show results on the console window if any communication error or Hardware error has been occurred.

% INDIRECTDATA parameter storages replace LED, goal position, present position and moving status storages
write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 0, ADDR_PRO_GOAL_POSITION + 0);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 2, ADDR_PRO_GOAL_POSITION + 1);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 4, ADDR_PRO_GOAL_POSITION + 2);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 6, ADDR_PRO_GOAL_POSITION + 3);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 8, ADDR_PRO_LED_RED);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

These allocate five target address for writing (ADDR_PRO_GOAL_POSITION + 0, ADDR_PRO_GOAL_POSITION + 1, ADDR_PRO_GOAL_POSITION + 2, ADDR_PRO_GOAL_POSITION + 3 and ADDR_PRO_LED_RED) to the Indirect Addresses(ADDR_PRO_INDIRECTADDRESS_FOR_WRITE + 0 ~ 9) 2 bytes each. Now, you can change goal position value or red LED value by writing 4 byte and 1 byte each on the 1st ~ 4th and 5th Indirect Data item.

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 0, ADDR_PRO_PRESENT_POSITION + 0);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 2, ADDR_PRO_PRESENT_POSITION + 1);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 4, ADDR_PRO_PRESENT_POSITION + 2);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 6, ADDR_PRO_PRESENT_POSITION + 3);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

write2ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_INDIRECTADDRESS_FOR_READ + 8, ADDR_PRO_MOVING);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

These allocate five target address for writing (ADDR_PRO_PRESENT_POSITION + 0, ADDR_PRO_PRESENT_POSITION + 1, ADDR_PRO_PRESENT_POSITION + 2, ADDR_PRO_PRESENT_POSITION + 3 and ADDR_PRO_MOVING) to the Indirect Addresses(ADDR_PRO_INDIRECTADDRESS_FOR_READ + 0 ~ 9) 2 bytes each. Now, you can get present position value or moving status value by reading 4 byte and 1 byte each on the 6st ~ 9th and 10th Indirect Data item.

% Enable Dynamixel Torque
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_ENABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

As mentioned in the document, above code enables each Dynamixel`s torque to set their status as being ready to move.

write1ByteTxRx() function orders to the #DXL_ID Dynamixel in PROTOCOL_VERSION communication protocol through #port_num port, writing 1 byte of TORQUE_ENABLE value to ADDR_PRO_TORQUE_ENABLE address. The function checks Tx/Rx result and receives Hardware error. getLastTxRxResult() function and getLastRxPacketError() function get either, and then printTxRxResult() function and printRxPacketError() function show results on the console window if any communication error or Hardware error has been occurred.

% Add parameter storage for the present position value
dxl_addparam_result = groupSyncReadAddParam(groupread_num, DXL_ID);
if dxl_addparam_result ~= true
  fprintf('[ID:%03d] groupSyncRead addparam failed', DXL1_ID);
  return;
end

groupSyncReadAddParam() function stores the Dynamixel ID of required data to the syncread target Dynamixel list.

while 1
    if input('Press any key to continue! (or input e to quit!)\n', 's') == ESC_CHARACTER
        break;
    end

    % Add values to the Syncwrite storage
    dxl_addparam_result = groupSyncWriteAddParam(groupwrite_num, DXL_ID, typecast(int32(dxl_goal_position(index)), 'uint32'), LEN_PRO_GOAL_POSITION);
    if dxl_addparam_result ~= true
        fprintf('[ID:%03d] groupSyncWrite addparam failed', DXL1_ID);
        return;
    end
    dxl_addparam_result = groupSyncWriteAddParam(groupwrite_num, DXL_ID, dxl_led_value(index), LEN_PRO_LED_RED);
    if dxl_addparam_result ~= true
        fprintf('[ID:%03d] groupSyncWrite addparam failed', DXL1_ID);
        return;
    end

    % Syncwrite all
    groupSyncWriteTxPacket(groupwrite_num);
    if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
        printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
    end

    % Clear syncwrite parameter storage
    groupSyncWriteClearParam(groupwrite_num);

    while 1
      % Syncread present position from indirectdata2
      groupSyncReadTxRxPacket(groupread_num);
      if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
          printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
      end

      % Check if groupsyncread data of Dyanamixel is available
      dxl_getdata_result = groupSyncReadIsAvailable(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_PRESENT_POSITION);
      if dxl_getdata_result ~= true
        fprintf('[ID:%03d] groupSyncRead getdata failed', DXL1_ID);
        return;
      end

      % Check if groupsyncread data of Dyanamixel is available
      dxl_getdata_result = groupSyncReadIsAvailable(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ + LEN_PRO_PRESENT_POSITION, LEN_PRO_MOVING);
      if dxl_getdata_result ~= true
        fprintf('[ID:%03d] groupSyncRead getdata failed', DXL1_ID);
        return;
      end

      % Get Dynamixel present position value
      dxl_present_position = groupSyncReadGetData(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ, LEN_PRO_PRESENT_POSITION);

      % Get Dynamixel moving status value
      dxl_moving = groupSyncReadGetData(groupread_num, DXL_ID, ADDR_PRO_INDIRECTDATA_FOR_READ + LEN_PRO_PRESENT_POSITION, LEN_PRO_MOVING);

      fprintf('[ID:%03d] GoalPos:%d  PresPos:%d  IsMoving:%d\n', DXL_ID, dxl_goal_position(index), typecast(uint32(dxl_present_position), 'int32'), dxl_moving);

      if ~(abs(dxl_goal_position(index) - typecast(uint32(dxl_present_position), 'int32')) > DXL_MOVING_STATUS_THRESHOLD)
        break;
      end
    end

    % Change goal position
    if index == 1
        index = 2;
    else
        index = 1;
    end
end

During while loop, the controller writes and reads each Dynamixel position through packet transmission/reception(Tx/Rx).

To continue their rotation, press any key except ESC.

groupSyncWriteAddParam() function stores the Dynamixel ID and its goal position dxl_goal_position and LED value dxl_led_value to the syncwrite target Dynamixel list.

groupSyncWriteTxPacket() function orders to the Dynamixel #DXL_ID through the port, making it possible to write same pre-listed length bytes to same pre-listed address. The function checks Tx/Rx result. getLastTxRxResult() function get it, and then printTxRxResult() function shows result on the console window if any communication error has been occurred.

groupSyncWriteClearParam() function clears the Dynamixel list of groupsyncwrite.

groupSyncReadTxRxPacket() function orders to the Dynamixel #DXL_ID through #port_num port, making it possible to read same pre-listed length(LEN_PRO_INDIRECTDATA_FOR_READ) of bytes to same pre-listed address(ADDR_PRO_INDIRECTDATA_FOR_READ). The function checks Tx/Rx result. getLastTxRxResult() function gets it, and then printTxRxResult() function shows result on the console window if any communication error has been occurred.

groupSyncReadIsAvailable() function checks if available data is in the groupsyncread data storage. The function returns false if no data is available in the storage.

groupSyncReadGetData() function pop the data received by groupSyncReadTxRxPacket() function out. In the example, it stores LEN_PRO_PRESENT_POSITION byte data and LEN_PRO_MOVING byte data got from ADDR_PRO_INDIRECTDATA_FOR_READ address of Dynamixel.

groupSyncReadClearParam() function clears the Dynamixel list of groupsyncread.

Reading their present position will be ended when absolute value of (dxl_goal_position[index] - dxl_present_position) becomes smaller then DXL_MOVING_STATUS_THRESHOLD.

At last, it changes their direction to the counter-wise and waits for extra key input.

% Disable Dynamixel Torque
write1ByteTxRx(port_num, PROTOCOL_VERSION, DXL_ID, ADDR_PRO_TORQUE_ENABLE, TORQUE_DISABLE);
if getLastTxRxResult(port_num, PROTOCOL_VERSION) ~= COMM_SUCCESS
    printTxRxResult(PROTOCOL_VERSION, getLastTxRxResult(port_num, PROTOCOL_VERSION));
elseif getLastRxPacketError(port_num, PROTOCOL_VERSION) ~= 0
    printRxPacketError(PROTOCOL_VERSION, getLastRxPacketError(port_num, PROTOCOL_VERSION));
end

The controller frees the Dynamixel to be idle.

write1ByteTxRx() function orders to the #DXL_ID Dynamixel in PROTOCOL_VERSION communication protocol through #port_num port, writing 1 byte of TORQUE_DISABLE value to ADDR_PRO_TORQUE_ENABLE address. The function checks Tx/Rx result and receives Hardware error. getLastTxRxResult() function and getLastRxPacketError() function get either, and then printTxRxResult() function and printRxPacketError() function show results on the console window if any communication error or Hardware error has been occurred.

% Close port
closePort(port_num);

Finally, port becomes disposed.

% Unload Library
unloadlibrary('dxl_x86_c');

Unload the library to make it reaccessible.