Robotis 2XL430-W250 User manual

2XL430-W250
1. Specifications
2XL430-W250 is a ground breaking DYNAMIXEL that allows to control 2 axis(2 DOF) with a single
module. In order to control 2 axis at the same time, each axle should be assigned with different ID
while sharing an identical Baudrate. Since the Control Table for each axle is separated except the
Baudrate, 2XL can be applied in various applications.
The usage is identical to other DYNAMIXEL’s, but be aware that Firmware Recovery will reset both
axis to factory settings.
Item Specifications
MCU ARM CORTEX-M3 (72 [MHz], 32Bit)
Position Sensor Contactless absolute encoder (12Bit, 360 [°])
Maker : ams(www.ams.com), Part No : AS5601
Motor Cored
Baud Rate 9,600 [bps] ~ 4.5 [Mbps]
Control Algorithm PID control
Resolution 4096 [pulse/rev]
Operating Modes
Velcoity Control Mode
Position Control Mode (0 ~ 360 [°])
Extended Position Control Mode (Multi-turn)
PWM Control Mode (Voltage Control Mode)
Weight 98.2 [g]
Dimensions (W x H x D) 36 x 46.5 x 36 [mm]
Gear Ratio 257.4 : 1
Stall Torque
1.0 [N.m] (at 9.0 [V], 1.0 [A])
1.4 [N.m] (at 11.1 [V], 1.3 [A])
1.5 [N.m] (at 12.0 [V], 1.4 [A])

Item Specifications
No Load Speed
47 [rev/min] (at 9.0 [V])
57 [rev/min] (at 11.1 [V])
61 [rev/min] (at 12.0 [V])
Operating Temperature -5 ~ +72 [°C]
Input Voltage 6.5 ~ 12.0 [V] (Recommended : 11.1 [V])
Command Signal Digital Packet
Protocol Type TTL Half Duplex Asynchronous Serial Communication
(8bit, 1stop, No Parity)
Physical Connection TTL Multidrop Bus
ID 253 ID (0 ~ 252)
Feedback Position, Velocity, Load, Realtime tick, Trajectory, Temperature, Input Voltage, etc
Part Material Full Metal Gear
Engineering Plastic(Front, Middle, Back)
Standby Current 49 [mA]
DANGER
(May cause serious injury or death)
Never place items containing water, flammables, and solvents near product.
Never place fingers, arms, toes, and other body parts near product during operation.
Cut power off if product emits strange odors or smoke.
Keep product out of reach of children.
Check the power polarity before wiring.
CAUTION
(May cause injury or damage to product)
Do not operate the product at a temperature exceeding -5 ~ +72 [°C] range.
Do not insert sharp blades nor pins during product operation.
ATTENTION
(May cause injury or damage to product)
Do not disassemble or modify product.
Do not drop or apply strong shock to product.

1. 1. Performance Graph
NOTE : The Max Torque and the Stall Torque of Performance Graph are different in measurement
methods. Stall torque is a measured value of the momentary torque that it can reach. This is
generally how RC servos are measured. The Performance graph is also called as N-T curves,
which is measured with the gradually increasing load. The actual motor operation environment is
closer to the performance graph, not stall torque method. For this reason, the performance graph is
broadly used in the industrial field. Generally, Max Torque of the Performance Graph is less than
the Stall Torque.
CAUTION : When supplying power
It is recommended using ROBOTIS controller or SMPS2DYNAMIXEL.
Do not connect or disconnect DYNAMIXEL when power is being supplied.
2. Control Table
The Control Table is a structure of data implemented in the device. Users can read a specific
Data to get status of the device with Read Instruction Packets, and modify Data as well to
control the device with WRITE Instruction Packets.
2. 1. Control Table, Data, Address
The Control Table is a structure that consists of multiple Data fields to store status or to
control the device. Users can check current status of the device by reading a specific Data
from the Control Table with Read Instruction Packets. WRITE Instruction Packets enable
users to control the device by changing specific Data in the Control Table. The Address is a

unique value when accessing a specific Data in the Control Table with Instruction Packets. In
order to read or write data, users must designate a specific Address in the Instruction
Packet. Please refer to Protocol 2.0 for more details about Instruction Packets.
NOTE : Two’s complement is applied for the negative value. For more information, please refer to
Two’s complement from Wikipedia.
2. 1. 1. Area (EEPROM, RAM)
The Control Table is divided into 2 Areas. Data in the RAM Area is reset to initial values
when the power is reset(Volatile). On the other hand, data in the EEPROM Area is
maintained even when the device is powered off(Non-Volatile).
Data in the EEPROM Area can only be written to if Torque Enable(64) is cleared to ‘0’(Off).
2. 1. 2. Size
The Size of data varies from 1 ~ 4 bytes depend on their usage. Please check the size of
data when updating the data with an Instruction Packet. For data larger than 2 bytes will
be saved according to Little Endian.
2. 1. 3. Access
The Control Table has two different access properties. ‘RW’ property stands for read and
write access permission while ‘R’ stands for read only access permission. Data with the
read only property cannot be changed by the WRITE Instruction. Read only property(‘R’)
is generally used for measuring and monitoring purpose, and read write property(‘RW’) is
used for controlling device.
2. 1. 4. Initial Value
Each data in the Control Table is restored to initial values when the device is turned on.
Default values in the EEPROM area are initial values of the device (factory default
settings). If any values in the EEPROM area are modified by a user, modified values will
be restored as initial values when the device is turned on. Initial Values in the RAM area
are restored when the device is turned on.
2. 2. Control Table of EEPROM Area
Address Size
(Byte) Data Name Access Default Value Range Unit
0 2 Model Number R 1,090 - -
2 4 Model Information R - - -
6 1 Firmware Version R - - -
7 1 ID RW 1, 2 0 ~ 253 -

Address Size
(Byte) Data Name Access Default Value Range Unit
8 1 Baud Rate RW 1 0 ~ 7 -
9 1 Return Delay Time RW 250 0 ~ 254 2 [μsec]
10 1 Drive Mode RW 0 0 ~ 1 -
11 1 Operating Mode RW 3 0 ~ 16 -
12 1 Secondary(Shadow) ID RW 255 0 ~ 252 -
13 1 Protocol Type RW 2 1 ~ 2 -
20 4 Homing Offset RW 0 -1,044,479 ~
1,044,479 1 [pulse]
24 4 Moving Threshold RW 10 0 ~ 1,023 0.229 [rev/min]
31 1 Temperature Limit RW 72 0 ~ 100 1 [°C]
32 2 Max Voltage Limit RW 140 60 ~ 140 0.1 [V]
34 2 Min Voltage Limit RW 60 60 ~ 140 0.1 [V]
36 2 PWM Limit RW 885 0 ~ 885 0.113 [%]
44 4 Velocity Limit RW 250 0 ~ 1,023 0.229 [rev/min]
48 4 Max Position Limit RW 4,095 0 ~ 4,095 1 [pulse]
52 4 Min Position Limit RW 0 0 ~ 4,095 1 [pulse]
63 1 Shutdown RW 52 - -
2. 3. Control Table of RAM Area
Address Size
(Byte) Data Name Access Default Value Range Unit
64 1 Torque Enable RW 0 0 ~ 1 -
65 1 LED RW 0 0 ~ 1 -
68 1 Status Return Level RW 2 0 ~ 2 -
69 1 Registered Instruction R 0 0 ~ 1 -
70 1 Hardware Error Status R 0 - -
76 2 Velocity I Gain RW 1,800 0 ~ 16,383 -
78 2 Velocity P Gain RW 100 0 ~ 16,383 -
80 2 Position D Gain RW 2,000 0 ~ 16,383 -
82 2 Position I Gain RW 0 0 ~ 16,383 -
84 2 Position P Gain RW 640 0 ~ 16,383 -
88 2 Feedforward 2nd Gain RW 0 0 ~ 16,383 -

Address Size
(Byte) Data Name Access Default Value Range Unit
90 2 Feedforward 1st Gain RW 0 0 ~ 16,383 -
98 1 Bus Watchdog RW 0 1 ~ 127 20 [msec]
100 2 Goal PWM RW - -PWM Limit(36) ~
PWM Limit(36) -
104 4 Goal Velocity RW - -Velocity Limit(44) ~
Velocity Limit(44) 0.229 [rev/min]
108 4 Profile Acceleration RW 0 0 ~ 32,767
0 ~ 32,737
214.577 [rev/min2]
1 [ms]
112 4 Profile Velocity RW 0 0 ~ 32,767 0.229 [rev/min]
116 4 Goal Position RW - Min Position Limit(52) ~
Max Position Limit(48) 1 [pulse]
120 2 Realtime Tick R - 0 ~ 32,767 1 [msec]
122 1 Moving R 0 0 ~ 1 -
123 1 Moving Status R 0 - -
124 2 Present PWM R - - -
126 2 Present Load R - -1,000 ~ 1,000 0.1 [%]
128 4 Present Velocity R - - 0.229 [rev/min]
132 4 Present Position R - - 1 [pulse]
136 4 Velocity Trajectory R - - 0.229 [rev/min]
140 4 Position Trajectory R - - 1 [pulse]
144 2 Present Input Voltage R - - 0.1 [V]
146 1 Present Temperature R - - 1 [°C]
168 2 Indirect Address 1 RW 224 64 ~ 661 -
170 2 Indirect Address 2 RW 225 64 ~ 661 -
172 2 Indirect Address 3 RW 226 64 ~ 661 -
… … … … … - -
218 2 Indirect Address 26 RW 249 64 ~ 661 -
220 2 Indirect Address 27 RW 250 64 ~ 661 -
222 2 Indirect Address 28 RW 251 64 ~ 661 -
224 1 Indirect Data 1 RW 0 0 ~ 255 -
225 1 Indirect Data 2 RW 0 0 ~ 255 -
226 1 Indirect Data 3 RW 0 0 ~ 255 -

Address Size
(Byte) Data Name Access Default Value Range Unit
… … … … … - -
249 1 Indirect Data 26 RW 0 0 ~ 255 -
250 1 Indirect Data 27 RW 0 0 ~ 255 -
251 1 Indirect Data 28 RW 0 0 ~ 255 -
578 2 Indirect Address 29 RW 634 64 ~ 661 -
580 2 Indirect Address 30 RW 635 64 ~ 661 -
582 2 Indirect Address 31 RW 636 64 ~ 661 -
… … … … … - -
628 2 Indirect Address 54 RW 659 64 ~ 661 -
630 2 Indirect Address 55 RW 660 64 ~ 661 -
632 2 Indirect Address 56 RW 661 64 ~ 661 -
634 1 Indirect Data 29 RW 0 0 ~ 255 -
635 1 Indirect Data 30 RW 0 0 ~ 255 -
636 1 Indirect Data 31 RW 0 0 ~ 255 -
… … … … … - -
659 1 Indirect Data 54 RW 0 0 ~ 255 -
660 1 Indirect Data 55 RW 0 0 ~ 255 -
661 1 Indirect Data 56 RW 0 0 ~ 255 -
CAUTION : Protocol 1.0 does not support addresses greater than 256. Therefore, Indirect Address
29 ~ 56 and Indirect Data 29 ~ 56 can only be accessed with Protocol 2.0.
2. 4. Control Table Description
CAUTION : Data in the EEPROM Area can only be written when the value of Torque Enable(64) is
cleared to ‘0’.
CAUTION : Each motor on 2XL430 has its own control table. However the value of Baud Rate(8)
and Protocol Type(13), is always changed at the same time because there is only one
communication module in the actuator.
In addition, Torque Enable(64) must be set as “0” when changed.
2. 4. 1. Model Number(0)
This address stores model number of DYNAMIXEL.

2. 4. 2. Firmware Version(6)
This address stores firmware version of DYNAMIXEL.
2. 4. 3. ID(7)
The ID is a unique value in the network to identify each DYNAMIXEL with an Instruction
Packet. 0~252 (0xFC) values can be used as an ID, and 254(0xFE) is occupied as a
broadcast ID. The Broadcast ID(254, 0xFE) can send an Instruction Packet to all
connected DYNAMIXEL simultaneously.
NOTE : Please avoid using an identical ID for multiple DYNAMIXEL. You may face
communication failure or may not be able to detect DYNAMIXEL with an identical ID.
CAUTION : Please assign two different IDs for the 2XL430. Attempting to assign an identical ID
for each joint will result in Data Limit Error(0x06) of the status packet.
2. 4. 4. Baud Rate(8)
Baud Rate determines serial communication speed between a controller and
DYNAMIXEL.
Value Baud Rate Margin of Error
7 4.5M 0.000%
6 4M 0.000%
5 3M 0.000%
4 2M 0.000%
3 1M 0.000%
2 115,200 0.000%
1(Default) 57,600 0.000%
0 9,600 0.000%
NOTE : Less than 3% of the baud rate error margin will not affect to UART communication.
NOTE : For the stable communication with higher Baudrate, configure USB Latency value to the
lower.
USB Latency Setting
CAUTION : Only one Baud Rate can be used for the 2XL430. Attempting to change the Baud
Rate of one joint will also affect to the other joint.

2. 4. 5. Return Delay Time(9)
After the DYNAMIXEL receives an Instruction Packet, it delays transmitting the Status
Packet for Return Delay Time(9). For instance, if the Return Delay Time(9) is set to ‘10’,
the Status Packet will be returned after 20[μsec] when the Instruction Packet is received.
Unit Value Range Description
2[μsec] 0 ~ 254 Default value ‘250’(500[μsec]), Maximum 508[μsec]
2. 4. 6. Drive Mode(10)
This address configures Drive Mode of DYNAMIXEL.
Bit Item Description
Bit 7(0x80) - Unused, always ‘0’
Bit 6(0x40) - Unused, always ‘0’
Bit 5(0x20) - Unused, always ‘0’
Bit 4(0x10) - Unused, always ‘0’
Bit 3(0x08) - Unused, always ‘0’
Bit 2(0x04) Profile Configuration
[0] Velocity-based Profile: Create a Profile based on Velocity
[1] Time-based Profile: Create Profile based on time
※ Please refer to Profile Velocity(112)
Bit 1(0x02) - Unused, always ‘0’
Bit 0(0x01) Normal/Reverse Mode [0] Normal Mode: CCW(Positive), CW(Negative)
[1] Reverse Mode: CCW(Negative), CW(Positive)
NOTE : Time-based Profile is available from firmware V42.
NOTE : If the value of Bit 0(Normal/Reverse Mode) of the Drive Mode(10) is set to 1 ,
rotational direction is inverted.
Thus, Goal Position, Present Position will have a inverted direction.
This feature can be very useful when configuring symmetrical joint or wheel system.
2. 4. 7. Operating Mode(11)
Value Operating
Mode Description
1
Velocity
Control Mode
(0° ~ 360°)
This mode controls velocity and ideal for wheel operation.
This mode is identical to the Wheel Mode(endless) from existing
DYNAMIXEL.

Value Operating
Mode Description
3(Default) Position
Control Mode
This mode controls position and identical to the Joint Mode.
Operating position range is limited by Max Position Limit(48) and Min
Position Limit(52).
This mode is ideal for articulated robots that each joint rotates less than
360°.
4
Extended
Position
Control Mode
(Multi-turn)
This mode controls position and identical to Multi-turn Mode.
512 turns are supported(-256[rev] ~ 256[rev]) and ideal for multi-turn wrists
or conveyer systems or a system that requires an additional reduction gear.
16
PWM Control
Mode
(Voltage
Control Mode)
This mode directly controls PWM output (Voltage Control Mode)
NOTE : Switching Operating Mode will reset gains(PID, Feedfoward) properly to the selected
Operating Mode. The profile generator and limits will also be reset.
1. Profile Velocity(112), Profile Acceleration(108) : Reset to ‘0’
2. Goal PWM(100) : Reset to PWM Limit(36)
NOTE : PWM is the abbreviation for Pulse Width Modulation that modulates PWM Duty to
control motors.
It changes pulse width to control average supply voltage to the motor and this technique is
widely used in the motor control field.
1. PWM Control Mode is similar to the Wheel Mode of DYNAMIXEL AX and RX series.
2. Use Goal PWM(100) on PWM Control Mode in order to control supply voltage for
DYNAMIXEL.
NOTE : Present Position(132) represents 4 byte continuous range from -2,147,483,648 to
2,147,483,647 when Torque is turned off regardless of Operating Mode(11).
However, Present Position(132) will be reset to an absolute position value of one full rotation in
those cases:
1. When Operating Mode(11) is changed to Position Control Mode, Present Position(132) will
be reset to an absolute position value of a full rotation.
2. When torque is turned on in Position Control Mode, Present Position(132) will be reset to
an absolute position value of one full rotation.
3. When turning off the power supply on Extended Position Control Mode, Present
Position(132) will be reset to an absolute position value of one full rotation.
Present Position(132) value can be affected by Homing Offset(20) .
2. 4. 8. Secondary(Shadow) ID(12)

Set the DYNAMIXEL’s Secondary ID. Secondary ID(12) is a value to identify each
DYNAMIXEL, just like the ID(7). However, unlike ID(7), Secondary ID(12) is not a unique
value. Therefore, DYNAMIXEL with the same Secondary ID value form a group. The
differences between Secondary ID(12) and ID(7) are as follows :
1. Secondary ID(12) is not a unique value. i.e., a lot of DYNAMIXEL may have the same
Secondary ID value.
2. ID(7) has a higher priority than Secondary ID(12). i.e., if Secondary ID(12) and ID(7)
are the same, ID(7) will be applied first.
3. The EEPROM area of the Control Table cannot be modified with Secondary ID(12).
Only the RAM area can be modified.
4. If Instruction Packet ID is the same as Secondary ID(12), the Status Packet will not be
returned.
5. If the value of Secondary ID(12) is 253 or higher, the Secondary ID function is
deactivated.
Values Description
0 ~ 252 Activate Secondary ID function
253 ~ 255 Deactivate Secondary ID function, Default value ‘255’
The following are examples of operation when there are five DYNAMIXEL with ID (7) set
from 1 to 5.
1. Set all five DYNAMIXEL’ Secondary ID(12) to ‘5’.
2. Send Write Instruction Packet(ID = 1, LED(65) = 1).
3. Turn on LED of DYNAMIXEL with ID ‘1’ and return the Status Packet.
4. Send Write Instruction Packet(ID = 5, LED(65) = 1).
5. Turn on LED on five DYNAMIXEL. However, Status Packet of DYNAMIXEL with ID ‘5’
will be returned.
6. Set the Secondary ID(12) of all five DYNAMIXEL to ‘100’.
7. Send Write Instruction Packet(ID = 100, LED(65) = 0).
8. Turn off LED on five DYNAMIXEL. However, as there is no DYNAMIXEL with ID ‘100’,
Status Packet is not returned.
2. 4. 9. Protocol type(13)
Users can select DYNAMIXEL protocol type (1.0 and 2.0).
Even if Protocol 1.0 is selected, Protocol 2.0 Control Table will be used.
It is recommended to use an identical protocol type for multiple DYNAMIXEL.
Value Protocol
Type Compatible DYNAMIXEL
1 1.0 AX Series, DX Series, RX Series, EX Series, MX Series with Firmware below
v39
2(default) 2.0 MX-28/64/106 with Firmware v39 or above, X Series, PRO Series

WARNING : In order to change the Protocol Type to Protocol 1.0, please use DYNAMIXEL
Wizard 2.0 as R+ Manager 2.0 does not support Protocol 1.0.
NOTE : The protocol 2.0 is greatly enhanced from the protocol 1.0. Accessing some of the
Control Table area might be denied if protocol 1.0 is selected. This manual complies with
protocol 2.0. Please refer to the Protocol 1.0 and Protocol 2.0 of e-Manual for more details
about the protocol.
NOTE : Please refer to the Protocol Compatibility table for product.
CAUTION : Only one Protocol Type can be used for the 2XL430. Attempting to change the
Protocol Type of one joint will also affect to the other joint.
2. 4. 10. Homing Offset(20)
Users can adjust the Home position by setting Home Offset(20). The Homing Offset value
is added to the Present Position(132).
Present Position(132) = Actual Position + Homing Offset(20)
Unit Value Range Description
about 0.088 [°] -1,044,479 ~ 1,044,479
(-255 ~ 255[rev]) 4,096 resolution
NOTE : In case of the Position Control Mode(Joint Mode) that rotates less than 360 degrees,
any invalid Homing Offset(20) values will be ignored(valid range : -1,024 ~ 1,024).
NOTE : In the case of Reverse Mode bit is set in Drive Mode(10), the sign of Homing Offset
value will not be reversed.
2. 4. 11. Moving Threshold(24)
This value helps to determine whether the DYNAMIXEL is in motion or not.
When the absolute value of Present Velocity(128) is greater than the Moving
Threshold(24), Moving(122) is set to ‘1’, otherwise it is cleared to ‘0’.
Values Description
Unit about 0.229 rpm All velocity related Data uses the same unit
Range 0 ~ 1,023 -
2. 4. 12. Temperature Limit(31)

This value limits operating temperature.
When the Present Temperature(146) that indicates internal temperature of DYNAMIXEL
is greater than the Temperature Limit(31), the Over Heating Error Bit(0x04) and Hardware
Error Bit(0x80) in the Hardware Error Status(70) will be set.
If Overheating Error Bit(0x04) is configured in the Shutdown(63), Torque Enable(64) is
cleared to ‘0’ and Torque will be disabled.
For more details, please refer to the Shutdown(63) section.
Unit Value Range Description
About 1° 0 ~ 100 0 ~ 100°
CAUTION : Do not set the temperature higher than the default value. When the temperature
alarm shutdown occurs, wait 20 minutes to cool the temperature before re-use. Keep using the
product when the temperature is high can cause severe damage.
2. 4. 13. Min/Max Voltage Limit(32, 34)
These values are maximum and minimum operating voltages.
When current input voltage acquired from Present Input Voltage(144) exceeds the range
of Max Voltage Limit(32) and Min Voltage Limit(34), Voltage Range Error Bit(0x01) and
Hardware Error Bit(0x80) in the Hardware Error Status(70) are set.
If Input Voltage Error Bit(0x10) is configured in the Shutdown(63), Torque Enable(64) is
cleared to ‘0’ and Torque is disabled.
For more details, please refer to the Shutdown(63) section.
Unit Value Range Description
About 0.1V 60 ~ 140 6.0 ~ 14.0V
2. 4. 14. PWM Limit(36)
This value indicates maximum PWM output. Goal PWM(100) can’t be configured with any
values exceeding PWM Limit(36). PWM Limit(36) is commonly used in all operating mode
as an output limit, therefore decreasing PWM output will result in decreasing torque and
velocity. For more details, please refer to the Gain section of each operating modes.
Values Description
0(0 [%]) ~ 885(100 [%]) 885 = 100 [%] output
2. 4. 15. Velocity Limit(44)
This indicates the maximum value of Goal Velocity(104). For more details, please refer to
Goal Velocity(104).
Unit Value Range
0.229rpm 0 ~ 1,023

NOTE: The default value of Velocity Limit(44) has been decreased since Firmware V42.
2. 4. 16. Min/Max Position Limit(48, 52)
These values limit maximum and minimum desired positions for Position Control
Mode(Joint Mode) within the range of 1 rotation(0 ~ 4,095).
Therefore, Goal Position(116) should be configured within the position limit range.
These values are not used in Extended Position Control Mode.
Unit Value Range
0.088 [°] 0 ~ 4,095(1 rotation)
NOTE : Max Position Limit(48) and Min Position Limit(52) are only used in Position Control
Mode with a single turn.
2. 4. 17. Shutdown(63)
The DYNAMIXEL can protect itself by detecting dangerous situations that could occur
during the operation.
Each Bit is inclusively processed with the ‘OR’ logic, therefore, multiple options can be
generated.
For instance, when ‘0x05’ (binary : 00000101) is defined in Shutdown(63), DYNAMIXEL
can detect both Input Voltage Error(binary : 00000001) and Overheating Error(binary :
00000100).
If those errors are detected, Torque Enable(64) is cleared to ‘0’ and the motor output
becomes 0 [%].
REBOOT is the only method to reset Torque Enable(64) to ‘1’(Torque ON) after the
shutdown.
Check Hardware Error Bit(0x80) in a error field of Status Packet or a present status via
Hardware Error Status(70) The followings are detectable situations.
Bit Item Description
Bit
7- Unused, Always ‘0’
Bit
6- Unused, Always ‘0’
Bit
5Overload Error(default) Detect persistent load that exceeds maximum output
Bit
4
Electrical Shock
Error(default)
Detect electric shock on the circuit or insufficient power to operate the
motor
Bit
3Motor Encoder Error Detect malfunction of the motor encoder

Bit Item Description
Bit
2OverHeating Error(default) Detect internal temperature exceeds the configured operating temperature
Bit
1- Unused, Always ‘0’
Bit
0Input Voltage Error Detect input voltage exceeds the configured operating voltage
NOTE :
1. If Shutdown occurs, LED will flicker every second. (Firmware v41 or above)
2. If Shutdown occurs, reboot the device.
H/W REBOOT : Turn off and turn on the power again
S/W REBOOT : Transmit REBOOT Instruction (For more details, refer to the Reboot
section of e-Manual.)
2. 4. 18. Torque Enable(64)
Controls Torque ON/OFF. Writing ‘1’ to this address will turn on the Torque and all Data in
the EEPROM area will be protected.
Value Description
0(Default) Turn off the torque
1 Turn on the torque and lock EEPROM area
NOTE : Present Position(132) can be reset when Operating Mode(11) and Torque Enable(64)
are updated. For more details, please refer to the Homing Offset(20) and Present Position(132).
2. 4. 19. LED(65)
Turn on or turn off the LED on DYNAMIXEL.
Bit Description
0(Default) Turn OFF the LED
1 Turn ON the LED
NOTE : The LED indicates present status of the device.
Status LED Representation
Booting LED flickers once
Factory Reset LED flickers 4 times
Alarm LED flickers
Boot Mode LED On

2. 4. 20. Status Return Level(68)
This value decides how to return Status Packet when DYNAMIXEL receives an
Instruction Packet.
Value Responding Instructions Description
0 PING Instruction Status Packet will not be returned for all Instructions
1PING Instruction
READ Instruction Status Packet will be returned only for READ Instruction
2 All Instructions Status Packet will be returned for all Instructions
NOTE : If the ID of Instruction Packet is set to Broad Cast ID(0xFE), Status Packet will not be
returned for READ and WRITE Instructions regardless of Status Return Level. For more details,
please refer to the Status Packet section for Protocol 1.0 or Protocol 2.0.
2. 4. 21. Registered Instruction(69)
Value Description
0 REG_WRITE instruction is not received
1 REG_WRITE instruction is received
NOTE : If ACTION instruction is executed, the value will be changed to 0.
2. 4. 22. Hardware Error Status(70)
The DYNAMIXEL can protect itself by detecting dangerous situations that could occur
during the operation.
Each Bit is inclusively processed with the ‘OR’ logic, therefore, multiple options can be
generated.
For instance, when ‘0x05’ (binary : 00000101) is defined in Shutdown(63), DYNAMIXEL
can detect both Input Voltage Error(binary : 00000001) and Overheating Error(binary :
00000100).
If those errors are detected, Torque Enable(64) is cleared to ‘0’ and the motor output
becomes 0 [%].
REBOOT is the only method to reset Torque Enable(64) to ‘1’(Torque ON) after the
shutdown.
Check Hardware Error Bit(0x80) in a error field of Status Packet or a present status via
Hardware Error Status(70) The followings are detectable situations.
Bit Item Description
Bit
7- Unused, Always ‘0’

Bit Item Description
Bit
6- Unused, Always ‘0’
Bit
5Overload Error(default) Detect persistent load that exceeds maximum output
Bit
4
Electrical Shock
Error(default)
Detect electric shock on the circuit or insufficient power to operate the
motor
Bit
3Motor Encoder Error Detect malfunction of the motor encoder
Bit
2OverHeating Error(default) Detect internal temperature exceeds the configured operating temperature
Bit
1- Unused, Always ‘0’
Bit
0Input Voltage Error Detect input voltage exceeds the configured operating voltage
NOTE :
1. If Shutdown occurs, LED will flicker every second. (Firmware v41 or above)
2. If Shutdown occurs, reboot the device.
H/W REBOOT : Turn off and turn on the power again
S/W REBOOT : Transmit REBOOT Instruction (For more details, refer to the Reboot
section of e-Manual.)
2. 4. 23. Velocity PI Gain(76, 78)
These values indicate Gains of Velocity Control Mode.
Gains of DYNAMIXEL’s internal controller can be calculated from Gains of the Control
Table as shown below.
The constant in each equations include sampling time.
Velocity P Gain of DYNAMIXEL’s internal controller is abbreviated to KVP and that of the
Control Table is abbreviated to KVP(TBL).
Controller Gain Conversion Equations Range Description
Velocity I Gain(76) KVI KVI = KVI(TBL) / 65,536 0 ~ 16,383 I Gain
Velocity P Gain(78) KVP KVP = KVP(TBL) / 128 0 ~ 16,383 P Gain
Below figure is a block diagram describing the velocity controller in Velocity Control Mode.
When the instruction transmitted from the user is received by DYNAMIXEL, it takes
following steps until driving the horn.
1. An Instruction from the user is transmitted via DYNAMIXEL bus, then registered to
Goal Velocity(104).

2. Goal Velocity(104) is converted to desired velocity trajectory by Profile
Acceleration(108).
3. The desired velocity trajectory is stored at Velocity Trajectory(136).
4. PI controller calculates PWM output for the motor based on the desired velocity
trajectory.
5. Goal PWM(100) sets a limit on the calculated PWM output and decides the final PWM
value.
6. The final PWM value is applied to the motor through an Inverter, and the horn of
DYNAMIXEL is driven.
7. Results are stored at Present Position(132), Present Velocity(128), Present PWM(124)
and Present Load(126).
NOTE : Ka stands for Anti-windup Gain and β is a conversion coefficient of position and velocity
that cannot be modified by users. For more details about the PID controller, please refer to the
PID Controller at wikipedia.
2. 4. 24. Position PID Gain(80, 82, 84), Feedforward 1st/2nd Gains(88, 90)
These Gains are used in Position Control Mode and Extended Position Control Mode.
Gains of DYNAMIXEL’s internal controller can be calculated from Gains of the Control
Table as shown below. The constant in each equations include sampling time. Position P
Gain of DYNAMIXEL’s internal controller is abbreviated to KPP and that of the Control
Table is abbreviated to KPP(TBL).
Controller
Gain
Conversion
Equations Range Description
Position D Gain(80) KPD KPD = KPD(TBL) / 16 0 ~
16,383 D Gain
Position I Gain(82) KPIKPI = KPI(TBL) /
65,536
0 ~
16,383 I Gain
Position P Gain(84) KPPKPP = KPP(TBL) /
128
0 ~
16,383 P Gain
Feedforward 2nd
Gain(88) KFF2nd KFF2nd(TBL) / 4 0 ~ 16,383
Feedforward Acceleration
Gain

Controller
Gain
Conversion
Equations Range Description
Feedforward 1st
Gain(90) KFF1st KFF1st(TBL) / 4 0 ~ 16,383 Feedforward Velocity Gain
Below figure is a block diagram describing the position controller in Position Control Mode
and Extended Position Control Mode. When the instruction from the user is received by
DYNAMIXEL, it takes following steps until driving the horn.
1. An Instruction from the user is transmitted via DYNAMIXEL bus, then registered to
Goal Position(116).
2. Goal Position(116) is converted to desired position trajectory and desired velocity
trajectory by Profile Velocity(112) and Profile Acceleration(108).
3. The desired position trajectory and desired velocity trajectory is stored at Position
Trajectory(140) and Velocity Trajectory(136) respectively.
4. Feedforward and PID controller calculate PWM output for the motor based on desired
trajectories.
5. Goal PWM(100) sets a limit on the calculated PWM output and decides the final PWM
value.
6. The final PWM value is applied to the motor through an Inverter, and the horn of
DYNAMIXEL is driven.
7. Results are stored at Present Position(132), Present Velocity(128), Present PWM(124)
and Present Load(126).
NOTE : In case of PWM Control Mode, both PID controller and Feedforward controller are
deactivated while Goal PWM(100) value is directly controlling the motor through an Inverter. In
this manner, users can directly control the supplying voltage to the motor.
NOTE : Ka is an Anti-windup Gain that cannot be modified by users.
For more details about the PID controller and Feedforward controller, please refer to the PID
Controller and Feed Forward.
2. 4. 25. Bus Watchdog(98)

Bus Watchdog (98) is available from firmware v38. It is a safety device (Fail-safe) that
stops the DYNAMIXEL if the communication between the controller and DYNAMIXEL
communication (RS485, TTL) is disconnected due to an unspecified error.
Communication is defined as all the Instruction Packet in the DYNAMIXEL Protocol.
Values Description
Unit 20[ms] -
Range 0 Deactivate Bus Watchdog Function, Clear Bus Watchdog Error
Range 1 ~ 127 Activate Bus Watchdog
Range -1 Bus Watchdog Error Status
The Bus Watchdog function monitors the communication interval (time) between the
controller and DYNAMIXEL when Torque Enable(64) is ‘1’. If the measured
communication interval (time) is larger than Bus Watchdog(98), the DYNAMIXEL will stop.
Bus Watchdog(98) will be changed to ‘-1’ (Bus Watchdog Error). If the Bus Watchdog
Error screen appears, the Goal Value (Goal PWM(100), Goal Velocity(104), Goal
Position(116)) will be changed to read-only-access. Therefore, when a new value is
written to the Goal Value, a Range Error will be returned via the Status packet. If the
value of Bus Watchdog(98) is changed to ‘0’, Bus Watchdog Error will be cleared.
NOTE : For details of Range Error, please refer to the protocol of the e-Manual.
The following are examples of the operation of the Bus Watchdog function.
1. After setting the Operating Mode(11) to speed control mode, change the Torque
Enable(64) to ‘1’.
2. If ‘50’ is written in the Goal Velocity(104), the DYNAMIXEL will rotate in CCW
direction.
3. Change the value of Bus Watchdog(98) to ‘100’ (2,000 [ms]). (Activate Bus Watchdog
Function)
4. If no instruction packet is received for 2,000 [ms], the DYNAMIXEL will stop. When it
stops, the Profile Acceleration(108) and Profile Velocity(112) are applied as ‘0’.
5. The value of Bus Watchdog(98) changes to ‘-1’ (Bus Watchdog Error). At this time, the
access to the Goal Value will be changed to read-only.
6. If ‘150’ is written to the Goal Velocity(104), Range Error will be returned via Status
Packet.
7. If the value of Bus Watchdog(98) is changed to ‘0’, Bus Watchdog Error will be
cleared.
8. If “150” is written in the Goal Velocity(104), the DYNAMIXEL will rotate in CCW
direction.
2. 4. 26. Goal PWM(100)