Revo 2 dexterous hand Communication Protocol Design

Revo 2 Touch Edition dexterous hand supports 3 types of external communication interfaces.：RS485、CAN FD、EtherCAT（Click here to learn about the EC protocol description.）Design a protocol compatible with both 485 and CAN FD communication interfaces, ensuring high efficiency, reliability, and scalability of communication based on compatibility with different communication protocols.

Communication Interface Features

RS485 Features

• Communication speed：Up to 10 Mbps, commonly used rate is 9600 bps~1 Mbps。
• Frame length: Supports variable-length frames, with the maximum frame length constrained by the specific application.
• Verification method：The software needs to implement CRC16 or checksum verification methods to adapt to complex electromagnetic environments.
• Communication mode：Half-duplex communication requires a collision detection mechanism.
• Reliability：Strong anti-interference ability, suitable for long-distance communication.

CAN FD Features

• Communication speed：The data segment rate can reach 5 Mbps, while the header maintains the traditional CAN speed.
• Frame length：Supports up to 64-byte data segments, extending CAN's data payload capability.
• Verification method：Hardware built-in verification, no software implementation required.
• Communication mode：Compatible with traditional CAN communication devices.

Compatibility Protocol Design

Modbus-RTU Protocol is a master-slave request-response communication protocol, widely used in industrial automation systems. The protocol frame includes an address, function code, data field, and CRC check to ensure the reliability of communication.

Data frame format：

Header/Device ID	Function Code	Data	CRC16
1byte	1byte	n bytes	2 Bytes

Header/Device ID: Device identifier, used to distinguish between different devices. Function Code: Function code, indicating the type of operation requested. Data: Data field, containing the data for the specific operation. CRC16: CRC check, used to verify the integrity of the data.

RS485Compatible Modbus RTU：

RS485 does not define a specific communication protocol itself, but is usually used in conjunction with the Modbus RTU protocol and is widely used for data transmission in industrial automation and monitoring systems.

CANFD Compatible Modbus RTU：

Canfd uses extended frames, and the arbitration frame baud rate is fixed at 1 MbThe data field in the CAN FD protocol can include the Device ID, master ID, and data length in the frame ID, and the data field contains the entire Modbus RTU format.

Host sends frame:

CAN FD ID（29bit）	Data (≤64Bytes）
24~28bit 0b00000 16~23bit Device ID 8~15bit Master ID 0 ~7bit Payload len	Header/Device ID	Function Code	Data	CRC16

Device response frame

CAN FD ID（29bit）	Data (≤64Bytes）
24~28bit 0b00000 16~23bit Device ID 8~15bit Master ID 0 ~7bit Payload len	Header/Device ID	Function Code	Data	CRC16

Function code

The function code is used to identify the type of operation requested. Each function code corresponds to a specific operation and is mainly used to read data from the device, write data, or perform other control tasks.

Function Code	Description
03H	Read Holding Registers
06H	Write Single Holding Register
10H	Write Multiple Holding Registers
04H	Read Input Registers

Registers

Hand Registers (Control Type)

Address	Type	Description	Length	Properties
900	Holding Register	Entry OTA	2 bytes	W
901	Holding Register	Left/Right Hand Read	2 bytes	R
902	Holding Register	Internal Gesture Restore Default	2 bytes	W
903	Holding Register	Restore Factory Settings	2 bytes	W
904	Holding Register	Backhand Light Switch	2 bytes	W/R
905	Holding Register	Buzzer Switch	2 bytes	W/R
906	Holding Register	Vibration Motor Switch	2 bytes	W/R
910	Holding Register	Factory KEY	20Bytes(10 uint16)	W/R
920	Holding Register	SN	20Bytes(10 uint16)	W/R
930	Holding Register	Thumb Flex Protection Current	2 bytes	W/R
931	Holding Register	Thumb Aux Protection Current	2 bytes	W/R
932	Holding Register	Index Finger Protection Current	2 bytes	W/R
933	Holding Register	Middle Finger Protection Current	2 bytes	W/R
934	Holding Register	Ring Finger Protection Current	2 bytes	W/R
935	Holding Register	Little Finger Protection Current	2 bytes	W/R
936	Holding Register	Thumb Aux Lock Current	2 bytes	W/R
937	Holding Register	Unit Mode Setting	2 bytes	W/R
938	Holding Register	Finger Minimum Position Setting	4 bytes	W
940	Holding Register	Finger Maximum Position Setting	4 bytes	W
942	Holding Register	Finger Maximum Speed Setting	4 bytes	W
944	Holding Register	Finger Maximum Current Setting	4 bytes	W
946	Holding Register	Finger Minimum Position Reading	12 bytes	R
952	Holding Register	Finger Maximum Position Reading	12 bytes	R
958	Holding Register	Finger Maximum Speed Reading	12 bytes	R
964	Holding Register	Finger Maximum Current Reading	12 bytes	R
970	Holding Register	Tactile Manufacturer	2 bytes	R
1000	Holding Register	Device ID	2 bytes	W/R
1001	Holding Register	RS485 Baud Rate	2 bytes	W/R
1002	Holding Register	CANFD Baud Rate	2 bytes	W/R
1003	Holding Register	CANFD arbitration field sample point configuration	2bytes	W/R
1009	Holding Register	Store Data/Restart	2 bytes	W/R
1010	Holding Register	Multi-Finger Position Time Control	24 bytes (12 uint16)	W/R
1022	Holding Register	Multi-Finger Position Speed Control	24 bytes (12 uint16)	W/R
1034	Holding Register	Multi-Finger Speed Control	12 bytes (6 uint16)	W/R
1040	Holding Register	Multi-Finger Current Control	12 bytes (6 uint16)	W/R
1046	Holding Register	Multi-Finger PWM Control	12 bytes (6 uint16)	W/R
1052	Holding Register	Single Finger Position Time Control	6 bytes (3 uint16)	W
1055	Holding Register	Single Finger Position Speed Control	6 bytes (3 uint16)	W
1058	Holding Register	Single Finger Speed Control	4 Bytes (2 uint16)	W
1060	Holding Register	Single Finger Current Control	4 Bytes (2 uint16)	W
1062	Holding Register	Single Finger PWM Control	4 Bytes (2 uint16)	W
1064	Holding Register	LED Settings	2 bytes	W/R
1065	Holding Register	Turbo Mode	2 bytes	W/R
1066	Holding Register	Turbo Mode Time Parameters	4 bytes	W/R
1068	Holding Register	Position Auto-Calibration	2 bytes	W/R
1069	Holding Register	Position Calibration	2 bytes	W
1070	Holding Register	Fast Position Control Mode	6 bytes (3 uint16)	W
1098	Holding Register	ACTION_CMD_ID	2bytes(1 uint16)	W
1099	Holding Register	ACTION_STEP_NUMBER	2bytes(1 uint16)	W/R
1100	Holding Register	ACTION_STEP_PARAMS	54bytes(27 uint16)	W/R
2000	Input Register	Actual Position Value	12 bytes (6 uint16)	R
2006	Input Register	Actual Speed Value	12 bytes (6 uint16)	R
2012	Input Register	Actual Current Value	12 bytes (6 uint16)	R
2018	Input Register	Motor Status	12 bytes (6 uint16)	R
2025	Input Register	Button Status	2 bytes	R
3000	Input Register	FW Version	20 bytes (10 uint16)	R
3010	Input Register	SN	20 bytes (10 uint16)	R

Tactile Module Register

Capacitive

Address	Type	Description	Length	Property
4000	Holding Register	Thumb Tactile Switch	2Byte	W/R
4001	Holding Register	Index Finger Tactile Switch	2Byte	W/R
4002	Holding Register	Middle Finger Tactile Switch	2Byte	W/R
4003	Holding Register	Ring Finger Tactile Switch	2Byte	W/R
4004	Holding Register	Little Finger Tactile Switch	2Byte	W/R
4005	Holding Register	Thumb Haptic Reset	2 bytes	w
4006	Holding Register	Index Finger Haptic Reset	2 bytes	w
4007	Holding Register	Middle Finger Haptic Reset	2 bytes	w
4008	Holding Register	Ring Finger Haptic Reset	2 bytes	w
4009	Holding Register	Little Finger Haptic Reset	2 bytes	w
4010	Holding Register	Thumb Haptic Parameter Calibration	2 bytes	w
4011	Holding Register	Index Finger Haptic Parameter Calibration	2 bytes	w
4012	Holding Register	Middle Finger Haptic Parameter Calibration	2 bytes	w
4013	Holding Register	Ring Finger Haptic Parameter Calibration	2 bytes	w
4014	Holding Register	Little Finger Haptic Parameter Calibration	2 bytes	w
4100	Input Register	Thumb Tactile Version	20 Bytes (10 uint16)	R
4110	Input Register	Index Finger Tactile Version	20 Bytes (10 uint16)	R
4120	Input Register	Middle Finger Tactile Version	20 Bytes (10 uint16)	R
4130	Input Register	Ring Finger Tactile Version	20 Bytes (10 uint16)	R
4140	Input Register	Little Finger Tactile Version	20 Bytes (10 uint16)	R
4200	Input Register	Multi-finger 3D Force	30 Bytes (15 uint16)	R
4215	Input Register	Multi-finger Proximity Value	20 Bytes (10 uint16)	R
4225	Input Register	Multi-finger Tactile Status	10 Bytes (5 uint16)	R
4250	Input Register	Thumb 3D Force, Proximity Value, Tactile Status	12 Bytes (6 uint16)	R
4256	Input Register	Index Finger 3D Force, Proximity Value, Tactile Status	12 Bytes (6 uint16)	R
4262	Input Register	Middle Finger 3D Force, Proximity Value, Tactile Status	12 Bytes (6 uint16)	R
4268	Input Register	Ring Finger 3D Force, Proximity Value, Tactile Status	12 Bytes (6 uint16)	R
4274	Input Register	Little Finger 3D Force, Proximity Value, Tactile Status	12 Bytes (6 uint16)	R
4300	Input Register	Thumb Tactile Raw Data	24 bytes (12 uint16)	R
4312	Input Register	Index Finger Tactile Raw Data	24 bytes (12 uint16)	R
4324	Input Register	Middle Finger Tactile Raw Data	24 bytes (12 uint16)	R
4336	Input Register	Ring Finger Tactile Raw Data	24 bytes (12 uint16)	R
4348	Input Register	Little Finger Tactile Raw Data	24 bytes (12 uint16)	R

Pressure Sensing

Starting Address	Register Type	Name	Data Length	Description	Attributes
6000	Holding Register	Tactile Data Type	2 Bytes	0: Raw Value 1: Calibrated Value	W/R
6005	Input Register	Five-Finger Combined Force	10 Bytes	5 fingers, 2 bytes per point	R
6010	Input Register	Thumb Tactile Data	18 Bytes	9 points, 2 bytes per point	R
6019	Input Register	Index Finger Tactile Data	18 Bytes	9 points, 2 bytes per point	R
6028	Input Register	Middle Finger Tactile Data	18 Bytes	9 points, 2 bytes per point	R
6037	Input Register	Ring Finger Tactile Data	18 Bytes	9 points, 2 bytes per point	R
6046	Input Register	Little Finger Tactile Data	18 Bytes	9 points, 2 bytes per point	R
6070	Input Register	Thumb Haptic Firmware Version	10 Bytes	Firmware version string (vx.x.x)	R
6080	Input Register	Index Finger Haptic Firmware Version	10 Bytes	Firmware version string (vx.x.x)	R
6090	Input Register	Middle Finger Haptic Firmware Version	10 Bytes	Firmware version string (vx.x.x)	R
6100	Input Register	Ring Finger Haptic Firmware Version	10 Bytes	Firmware version string (vx.x.x)	R
6110	Input Register	Little Finger Haptic Firmware Version	10 Bytes	Firmware version string (vx.x.x)	R
6130	Holding Register	Thumb Haptic Switch	2 Bytes	0: Off; 1: On	W/R
6131	Holding Register	Index Finger Haptic Switch	2 Bytes	0: Off; 1: On	W/R
6132	Holding Register	Middle Finger Haptic Switch	2 Bytes	0: Off; 1: On	W/R
6133	Holding Register	Ring Finger Haptic Switch	2 Bytes	0: Off; 1: On	W/R
6134	Holding Register	Little Finger Haptic Switch	2 Bytes	0: Off; 1: On	W/R

Register Description

Enter OTA/900

The settings take effect immediately after entering OTA.After entering OTA mode, pass throughUpgrade Agreement perform transmission mirroring.After the transmission is completed, the device enters bootloader mode to copy the firmware. Once the copy is finished, it automatically restarts and enters the normal program.

Parameter Setting	Meaning
1	Enter OTA mode

Left and Right Hand Reading / 901

To distinguish left and right hands, a register is used to read the current device's hand information.

Register Address	Purpose	Value
901	Hand Recognition	1: Right Hand 2: Left Hand

Restore Default Values for Internal Gesture Sequence /902

Register Address	Purpose	Type	Write Value	Function Description
902	Restore default values for 6 internal gestures	W	0x5A5A	Restore default values for 6 internal gestures

• Writing the fixed value 0x5A5A to register 902 can trigger the device to restore all internal gesture sequences to factory default values.
• Changes take effect and are saved immediately after restoring default gestures, and the default gesture configuration remains even after the device is restarted.

Factory Reset Register /903

Register Address	Purpose	Type	Write Value	Function Description
903	Factory Reset	W	0xA5A5	Performs factory reset

• Writing the fixed value 0xA5A5 to register 903 can trigger the device to restore factory settings.
• Default ID：Left hand → Reset to 0x7E（126）；Right hand → Reset to 0x7F（127）
• RS485 Baud rate: Reset to 460800 bps.
• CAN FD Baud rate: Reset to 5 Mbps.

Backlight Switch /904, Buzzer Switch /905, Vibration Motor Switch /906

Register Address	Name	Description	Value Range	Default
904	Backlight Switch	Controls the back LED light on the hand	0: Off 1: On	1
905	Buzzer Switch	Controls whether the buzzer sounds	0: Off 1: On	1
906	Vibration Motor Switch	Controls whether the vibration motor is enabled (vibration)	0: Off 1: On	0

Finger Protection Current Settings / 930-935

Register Address	Purpose	Corresponding Finger	Unit	Range	Default Value (mA)
930	Thumb FLEX Protection Current	Thumb Tip (FLEX)	mA	100 ～ 1500	500
931	Thumb AUX Protection Current	Thumb Base (AUX)	mA	100 ～ 1500	500
932	Index Finger Protection Current	Index Finger	mA	100 ～ 1500	500
933	Middle Finger Protection Current	Middle Finger	mA	100 ～ 1500	500
934	Ring Finger Protection Current	Ring Finger	mA	100 ～ 1500	500
935	Little Finger Protection Current	Little Finger	mA	100 ～ 1500	500

• This register can perform read and write operations, and is used to read and set the current protection threshold for the fingers.
• When writing the protection current, writing will be rejected if it exceeds the range.
• The written protection current is only effective during the current operation; it will automatically revert to the default value upon shutdown or restart.

Thumb AUX lock current /936

Register Address	Purpose	Type	Unit	Range	Default Value
936	Thumb AUX Lock Current Setting	W/R	mA	100-500	200

• The thumb AUX has no mechanical locking. Due to the rebound force of the wrinkled silicone, it is necessary to maintain the locking state using motor current.

Unit Mode Settings /937

Determine the units of input/output data for all fingers:

Value	Mode Name	Input/Output Format
0	Normalized Mode	0-1000 (no unit)
1	Physical Unit Mode	Angle (°), Speed (°/s), Current (mA)

• Mode Description：

Mode	Position Range	Speed Range	Current Input Range	Description
Normalized Mode	0-1000 (mapped to min-max position)	0-1000 (mapped to max speed)	0-1000 (mapped to max current)	Applicable for unitless control, where the master station does not need to care about specific hardware parameters
Physical Units Mode	Angle (°)	Angular Speed (°/s)	Current (mA)	Applicable for precise control, where physical values can be set directly

Finger maximum/minimum value settings /938-944

All settings for maximum/minimum positions, maximum speed, and maximum current need carry Motor number + Target value，Each setting occupies 2 bytes of registers.

** Starting address of the register **	Parameter type	Data format
938	Finger Minimum Position (°)	[Motor number] [Minimum position value]
940	Finger Maximum Position (°)	[Motor number] [Maximum position value]
942	Finger Maximum Speed (°/s)	[Motor number] [Maximum speed value]
944	Finger Maximum Current (mA)	[Motor number] [Maximum current value]

• Default values for each finger:

Finger Name	Motor Number	Default Minimum Position (°)	Default Maximum Position (°)	Default Maximum Speed (°/s)	Default Maximum Current (mA)
Thumb Flex	0	0°	59°	145°/s	1000mA
Thumb Aux	1	0°	90°	150°/s	1000mA
Index	2	0°	81°	130°/s	1000mA
Middle	3	0°	81°	130°/s	1000mA
Ring	4	0°	81°	130°/s	1000mA
Pinky	5	0°	81°	130°/s	1000mA

Description：

• Position angle The minimum and maximum values can be modified.，The default minimum value is 0°, but it can be adjusted dynamically.
• The minimum values of speed and current are fixed at 0, non-configurable, while the maximum values can be dynamically adjusted.
• After shutting down, all fingers’s Maximum/minimum position, maximum speed, and maximum current will all restore to default values.

Finger Max/Min Value Readings /946-964

Register Address	Purpose	Thumb Tip	Thumb Base	Index Finger	Middle Finger	Ring Finger	Little Finger
946 - 951	Minimum Position Readings (°)	946	947	948	949	950	951
952 - 957	Maximum Position Readings (°)	952	953	954	955	956	957
958 - 963	Maximum Speed Readings (°/s)	958	959	960	961	962	963
964 - 969	Maximum Current Readings (mA)	964	965	966	967	968	969

Description

1. Minimum/Maximum Position (°): Used to read the range of motion for each finger, where the minimum and maximum angles for each finger can be dynamically adjusted, but take effect only after powering on; they revert to default values after powering off.
2. Maximum Speed (°/s): Used to read the maximum speed of finger movement, which is configurable, but takes effect only after powering on; it reverts to default values after powering off.
3. Maximum Current (mA): Used to read the maximum allowable current for the finger drive motor, which is configurable, but takes effect only after powering on; it reverts to default values after powering off.

Haptic Vendor Type / 970

Address	Name	Read/Write Type	Description
970	Haptic Vendor Type	R	0: No haptics; 1: Capacitive; 2: Piezoresistive

Modify Device ID / 1000

Modify Device ID. The set range is: 1 - 254.After setting the ID, it takes effect immediately and is saved to flash.

Default ID: Left hand default ID is 0x7e, right hand default ID is 0x7f.

RS485 Device Baud Rate/1001

RS485 device baud rate, you can set the parameters below:

Setting Parameters	Baud Rate
0	115200
1	57600
2	19200
3	460800
4	1000000
5	2000000
6	5000000

CANFD Device Baud Rate/1002

The baud rate of the CANFD device can be set with the parameters below

Set Parameter	Baud Rate
0	100 kbps
1	125 kbps
2	200 kbps
3	250kbps
4	400kbps
5	500kbps
6	800kbps
7	1Mbps
8	2Mbps
9	4Mbps
10	5Mbps

CANFD Arbitration Field Sampling Point Configuration /1003

CANFD Arbitration domain sampling points can be set with the following parameters

Set parameters	Baud rate / Sampling point
0	1000 kbps 75% Sampling point
1	1000 kbps 80% Sampling point

** Restart/1009**

Set the Restart/1009 register, and the dexterous hand will restart.

Multiple Finger Position Time Control/1010

Each mechanical hand includes 6 motors, with the thumb driven by 2 motors. The table below lists the correspondence between registers and the motors for each finger.The value of the position register can be in a normalized range of 0 to 1000, or in an actual position range (unit: °).

To achieve a control precision of 0.1°, position values are uniformly scaled by a factor of 10 before being sent (i.e., 1 represents 0.1°). Here, 0 represents fully open, and 1000 represents fully closed.

The expected time register has a value range of 1 to 2000, with units in milliseconds (ms). When the set expected time is less than the fastest execution time allowed by the motor, the motor will operate at maximum speed.

Finger	Register Address	Register Value
Thumb Flex	Position Register 1010	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1011	1-2000
Thumb Aux	Position Register 1012	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1013	1-2000
Index Finger	Position Register 1014	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1015	1-2000
Middle Finger	Position Register 1016	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1017	1-2000
Ring Finger	Position Register 1018	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1019	1-2000
Little Finger	Position Register 1020	0 - 1000 or Minimum - Maximum Position (°)
	Expected Time Register 1021	1-2000

Multiple Finger Position Speed Control / 1022

Each robotic hand consists of 6 motors, with the thumb driven by 2 motors. The table below lists the correspondence between registers and the motors of each finger.The values of the position register can be either in the normalized range of 0 to 1000 or in actual angle range (unit: °).

To achieve a control precision of 0.1°, the position values are uniformly scaled up by a factor of 10 when issued (i.e., 1 represents 0.1°). Here, 0 represents fully open, while 1000 represents fully closed.

The expected speed register can be in a normalized range of 1 to 1000 or in the actual angular speed range (unit: °/s), which is used to control the rotation speed of the fingers.When the set expected speed exceeds the maximum speed of the motor, the motor will operate at its maximum speed.

Finger	Register Address	Register Value
Thumb Flex	Position Register 1022	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1023	1 - 1000 or Desired Speed (1-Maximum Speed °/s)
Thumb Aux	Position Register 1024	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1025	1 - 1000 or Desired Speed (1-Maximum Speed °/s)
Index Finger	Position Register 1026	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1027	1 - 1000 or Desired Speed (1-Maximum Speed °/s)
Middle Finger	Position Register 1028	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1029	1 - 1000 or Desired Speed (1-Maximum Speed °/s)
Ring Finger	Position Register 1030	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1031	1 - 1000 or Desired Speed (1-Maximum Speed °/s)
Little Finger	Position Register 1032	0 - 1000 or Minimum-Maximum Position (°)
	Desired Speed Register 1033	1 - 1000 or Desired Speed (1-Maximum Speed °/s)

Multiple Finger Speed Control/1034

The normalization mode is set to a range of -1000 to 1000, and the physical unit mode range is (-maximum speed - miximum speed), where the sign indicates the direction: positive indicates the gripping direction, and negative indicates the releasing direction. The unit of speed value in physical unit mode is: °/s

Register Address	Finger	Register Value
1034	Thumb Flex	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)
1035	Thumb Aux	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)
1036	Index Finger	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)
1037	Middle Finger	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)
1038	Ring Finger	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)
1039	Little Finger	-1000 - 1000 or Desired Speed (-maximum speed - miximum speed °/s)

Multi-finger Current Control / 1040

The normalization mode setting range is -1000 to 1000, and the physical unit mode range is (-maximum current - maximum current), where the sign indicates direction: positive for gripping direction and negative for releasing direction. The unit of the current value in physical unit mode is: mA

Register Address	Finger	Register Value
1040	Thumb Flex	-1000 to 1000 or expected current (-maximum current - maximum current)
1041	Thumb Aux	-1000 to 1000 or expected current (-maximum current - maximum current)
1042	Index Finger	-1000 to 1000 or expected current (-maximum current - maximum current)
1043	Middle Finger	-1000 to 1000 or expected current (-maximum current - maximum current)
1044	Ring Finger	-1000 to 1000 or expected current (-maximum current - maximum current)
1045	Little Finger	-1000 to 1000 or expected current (-maximum current - maximum current)

Multi-finger PWM Control / 1046

Finger PWM control, where the symbol indicates direction: positive indicates the gripping direction, and negative indicates the releasing direction.

Register Address	Finger	Register Value
1046	Thumb Flex	-1000 - 1000
1047	Thumb Aux	-1000 - 1000
1048	Index Finger	-1000 - 1000
1049	Middle Finger	-1000 - 1000
1050	Ring Finger	-1000 - 1000
1051	Little Finger	-1000 - 1000

Single Finger Position Time Control / 1052

In order to achieve a control precision of 0.1°, the position values are uniformly amplified by 10 times before being issued (i.e., 1 represents 0.1°).

Register Address	Register Name	Register Value
1052	Finger number	0-5
1053	position	1-1000 or Minimum - Maximum Position（°）
1054	Expected time	1- 2000

Single Finger Position Speed Control / 1055

In order to achieve a control precision of 0.1°, the position values are uniformly amplified by 10 times before being sent out in physical quantity mode (i.e., 1 represents 0.1°).

Register Address	Register Name	Register Value
1055	Finger number	0-5
1056	Position	0-1000 or minimum-Maximum position（°）
1057	Expected speed（°/s）	1 - 1000 or Expected speed（1-Maximum speed°/s）

Single Finger Speed Control/1058

Register Address	Register Name	Register Value
1058	Finger number	0-5
1059	Speed	-1000 - 1000 or Expected speed（-Maximum speed —— Miximum speed°/s）

Single finger current control / 1060

Register Address	Register Name	Register Value
1060	Finger number	0-5
1061	Current	-1000 - 1000或 Expected current (-maximum current —— maximum current mA)

Single finger PWM control/1062

Register Address	Register Name	Register Value
1062	Finger number	0-5
1063	PWM	-1000-1000

LED Control/1064

Register value

uint8_t led_mode = 1;
uint8_t led_color = 2;
uint16_t register_value = ((uint16_t)led_mode << 8) + led_color;

LED MODE	Description	Register Value
1	LED_MODE_SHUTDOWN	1
2	LED_MODE_KEEP	2
3	LED_MODE_BLINK	3
4	LED_MODE_ONE_SHOT	4
5	LED_MODE_BLINK0_5HZ	5
6	LED_MODE_BLINK2HZ	6

LED COLOR	Description	Register Value
1	LED_COLOR_R	1
2	LED_COLOR_G	2
3	LED_COLOR_RG	3
4	LED_COLOR_B	4
5	LED_COLOR_RB	5
6	LED_COLOR_GB	6
7	LED_COLOR_RGB	7

Turbo Mode/1065

Turbo mode resets to the default off state after power loss.

Register Value	Description
0	Off
1	On

Turbo mode time parameters / 1066

Turbo mode is implemented based on the stall feature, where the motor stops moving for a period of time (stall time) after the stall, then switches to a continue motion time, periodically executing stop and continue motion.

Register Address	Description
1066	Stall time, no movement, unit ms, default is 500 ms
1067	Continue motion time, unit ms, default is 500 ms

Position Auto Calibration / 1068

Position auto calibration retention register, used to enable or disable the dexterous hand to automatically perform position calibration after power-on. Position calibration refers to the process in which the dexterous hand searches for the starting position of the fingers after power-on, during which all fingers will be activated.

The valid values for this register are 1 and 0, where 1 enables position auto calibration, which is the default state; 0 disables position auto calibration.When position auto calibration is turned off, users need to perform manual position calibration.

There are two ways for manual position calibration: through the Position Calibration (1069) retention register, or by briefly pressing the backlight button after power-on.

Note1: During the position calibration process, if the dexterous hand has a grasped object, there may be a risk of dropping.

Note2: After powering on the dexterous hand, a position calibration must be performed to enable normal control.

Position Calibration/1069

The position calibration hold register; this command is only valid when 'Position Auto Calibration' (1068) is turned off. The valid value for this register is '1', which means to start position calibration.

Fast Position Control Mode/1070-1072

Fast control mode is a high-response mode with simplified inputs, achieving quick finger control by setting the percentage position value (0-100).

Register Address	Byte Offset	Corresponding Finger	Control Parameter	Description
1070	byte0	Thumb Base (Aux)	Percentage Position (0-100)	Position control at maximum speed
1070	byte1	Thumb Tip (Flex)	Percentage Position (0-100)	Position control at maximum speed
1071	byte0	Index Finger	Percentage Position (0-100)	Position control at maximum speed
1071	byte1	Middle Finger	Percentage Position (0-100)	Position control at maximum speed
1072	byte0	Ring Finger	Percentage Position (0-100)	Position control at maximum speed
1072	byte1	Little Finger	Percentage Position (0-100)	Position control at maximum speed

• Writing should be completed in one go for 3 registers (1070~1072), which is 6 bytes.
• The percentage position represents a normalized value relative to the minimum/maximum position range of the finger: 0 indicates the minimum position, and 100 indicates the maximum position.
• Ultimate goal perspective = Minimum position + percentage * (Maximum position - Minimum position) / 100

Action Sequence ACTION_CMD_ID/1098

Includes commands and action sequence Index. Action sequence

uint8_t cmd = 1;
uint8_t id = 2;
uint16_tregister_value = ((uint16_t)cmd << 8) + id;

CMD	Description
1	SET_START
2	SET_FINISH
3	READ_START
4	READ_FINISH
5	SAVE
6	RUN

Action ID	Description
1	Built-in open action	W/R
2	Built-in fist action	W/R
3	Built-in two-finger pinch gesture	W/R
4	Built-in three-finger pinch gesture	W/R
5	Built-in side pinch gesture	W/R
6	Built-in single-finger tap gesture	W/R
7	Gesture sequence 1	W/R
8	Gesture sequence 2	W/R
9	Gesture sequence 3	W/R
10	Gesture sequence 4	W/R
11	Gesture sequence 5	W/R
12	Gesture sequence 6	W/R
......	......	W/R
30	Gesture sequence 24	W/R

Action Step Count Register/1099

Readable and writable, indicates the number of steps included in the action. Maximum of 8.

Action Step Parameter Register/1100Readable and writable, this represents the sequence, time, position, speed, and force parameters in the action step, where position refers to the finger position (°). When the position is set to -1, it indicates that the finger maintains its original angle, and the speed refers to the finger rotation speed (°/s).

Register Address	Register Name	Description
1100	index	Indicates the action sequence, range 0-8	W/R
1101	duration_ms	Runtime	W/R
1102	ctrl type	Position time control: 1 Position speed control: 2 Current control: 3 Speed control: 4	W/R
1103	positions[0]	Thumb Flex position value	W/R
1104	positions[1]	Thumb Aux position value	W/R
1105	positions[2]	Index position value	W/R
1106	positions[3]	Middle finger position value	W/R
1107	positions[4]	Ring finger position value	W/R
1108	positions[5]	Little finger position value	W/R
1109	expect_interval[0]	Thumb Flex Position Control Movement Time	W/R
1110	expect_interval[1]	Thumb Aux Position Control Movement Time	W/R
1111	expect_interval[2]	Index Finger Position Control Movement Time	W/R
1112	expect_interval[3]	Middle Finger Position Control Movement Time	W/R
1113	expect_interval[4]	Ring Finger Position Control Movement Time	W/R
1114	expect_interval[5]	Little Finger Position Control Movement Time	W/R
1115	speed[0]		W/R
1116	speed[1]		W/R
1117	speed[2]		W/R
1118	speed[3]		W/R
1119	speed[4]		W/R
1120	speed[5]		W/R
1121	force[0]
1122	force[1]
1123	force[2]
1124	force[3]
1125	force[4]
1126	force[5]

Write the action sequence

Read action sequence

Actual Position Value / 2000

In order to achieve a control precision of 0.1°, the position values in physical quantity mode are uniformly amplified by 10 times before reporting (i.e., 1 represents 0.1°)

Register Address	Finger	Register Value
2000	Thumb Flex	0 - 1000 or Actual Angle (°)
2001	Thumb Aux	0 - 1000 or Actual Angle (°)
2002	Index Finger	0 - 1000 or Actual Angle (°)
2003	Middle Finger	0 - 1000 or Actual Angle (°)
2004	Ring Finger	0 - 1000 or Actual Angle (°)
2005	Little Finger	0 - 1000 or Actual Angle (°)

Actual Speed Values/2006

The speed value indicates the magnitude of speed, and the symbol indicates the direction of the motor finger movement.

Register Address	Finger	Register Value
2006	Thumb Flex	-1000-1000 or Actual Speed (°/s)
2007	Thumb Aux	-1000-1000 or Actual Speed (°/s)
2008	Index Finger	-1000-1000 or Actual Speed (°/s)
2009	Middle Finger	-1000-1000 or Actual Speed (°/s)
2010	Ring Finger	-1000-1000 or Actual Speed (°/s)
2011	Little Finger	-1000-1000 or Actual Speed (°/s)

Actual Current Value/2012

The current value indicates the magnitude of the current, and the symbol indicates the direction of finger movement for the motor.

Register Address	Finger	Register Value
2012	Thumb Flex	-1000-1000 or Actual current value (mA)
2013	Thumb Aux	-1000-1000 or Actual current value (mA)
2014	Index Finger	-1000-1000 or Actual current value (mA)
2015	Middle Finger	-1000-1000 or Actual current value (mA)
2016	Ring Finger	-1000-1000 or Actual current value (mA)
2017	Little Finger	-1000-1000 or Actual current value (mA)

Motor Status/2018

Register Address	Finger	Register Value
2018	Thumb Flex	0 - 3
2019	Thumb Aux	0 - 3
2020	Index Finger	0 - 3
2021	Middle Finger	0 - 3
2022	Ring Finger	0 - 3
2023	Little Finger	0 - 3

Register Value	Description
0	Motor Idle
1	Motor Running
2	Motor Stalled
3	Turbo

Key Status/2025

Read the key status. 0 means not pressed, 1 means pressed.

FW Version/3000

Read firmware version, 10 registers, maximum length of 20 strings.

The string is converted to multiple uint16_t registers in big-endian format.

Big-endian uint16_t	Char	String
0x302E, 0x302E, 0x342E, 0x5300	30 2E 30 2E 34 2E 53 00	0.0.4.S

SN/3010

Read SN version, 10 registers, maximum length of 20 characters.

The string is converted to multiple uint16_t registers in big-endian format.

Big-endian uint16_t	Char	String
0x534E, 0x3132, 0x3334, 0x3738, 0x3930, 0x3132, 0x3334, 0x3500	53 4E 31 32 33 34 35 36 37 38 39 30 31 32 33 34 35 00	SN123456789012345

Tactile Register Description - Capacitive

The fingertips of the capacitive tactile hand have tactile sensors. Due to structural differences in each finger, the arrangement of the fingers varies slightly; however, the data from each finger is collected through 6 channels, outputting a set of three-dimensional force and proximity force.

Configuration Register (Address Range: 4000–4014)

Address Range	Function Description	Data Width	Read/Write	Description
4000 Thumb 4001 Index Finger 4002 Middle Finger 4003 Ring Finger 4004 Little Finger	Haptic Switch Configuration	2Bytes	R/W	0: Off; 1: On
4005 Thumb 4006 Index Finger 4007 Middle Finger 4008 Ring Finger 4009 Little Finger	Haptic Channel Reset Command	2Bytes	W	Write 1 to trigger reset
4010 Thumb 4011 Index Finger 4012 Middle Finger 4013 Ring Finger 4014 Little Finger	Parameter Calibration Trigger	2Bytes	W	Write 1 to trigger finger parameter calibration

• Tactile Switch:The tactile switch supports the independent activation/deactivation of the tactile function of each finger. It supports read operations, where writing 1 indicates that the tactile of the corresponding finger is activated, and 0 indicates that the tactile of the corresponding finger is deactivated. Reading 1 means that the tactile channel is in the activated state, while 0 means that the tactile channel is in the deactivated state.

• Channel Reset:The Channel Reset register accepts an input value of 1 to trigger the sensor collection channel reset command. During the execution of this command, the finger sensor should not be subjected to force.

• Parameter CalibrationThe Parameter Calibration register accepts an input value of 1 to trigger the parameter calibration command. When the three-dimensional force values in the idle state are not 0, calibration can be performed through this register. The execution time of this command is relatively long, and data during this period cannot be used as a reference. It is recommended to ignore the data within ten seconds after setting the Parameter Calibration register. The finger sensor must not be subjected to force during the execution of this command, otherwise, the calibrated sensor data will be abnormal.

Tactile Firmware Version Information (Address Range: 4100–4140)

Address	Corresponding Finger	Data Width	Read/Write	Description
4100	Thumb	20 Bytes (10 uint16)	R	Firmware compilation date string
4110	Index Finger	20 Bytes (10 uint16)	R	Firmware compilation date string
4120	Middle Finger	20 Bytes (10 uint16)	R	Firmware compilation date string
4130	Ring Finger	20 Bytes (10 uint16)	R	Firmware compilation date string
4140	Little Finger	20 Bytes (10 uint16)	R	Firmware compilation date string

• Haptic firmware version informationThe version register is used to obtain the version of the haptic sensor, with a length of 10 registers. The string is converted to multiple uint16_t registers in big-endian format.

Five-finger three-dimensional force / proximity / tactile state (address range: 4200–4229)

Address Range	Data Type	Size per Pointer	Total Size	Order	Description
4200–4214	3D force data	6 Bytes	30 Bytes	Thumb → Pinky	法向力2B + 切向力2B + 方向角2B
4215–4224	Proximity value	4 Bytes	20 Bytes	Thumb → Pinky
4225–4229	Tactile state	2 Bytes	10 Bytes	Thumb → Pinky

• Normal and tangential forces are 16-bit unsigned data. The unit of measurement is 0.01 N, so a value of 1000 represents 10 N (1000 * 0.01 N). The measurement range is from 0 to 25 N.
• The direction of the tangential force is 16-bit unsigned data. The unit is in degrees, with a numeric range of 0 to 359 degrees. The direction close to the fingertip is 0 degrees, rotating clockwise to a maximum of 359 degrees. When the value is 65535 (0xFFFF), it indicates that the tangential force direction is invalid.
• Proximity value is 32-bit unsigned data.
• The tactile state register is 16 bits, with high and low bytes representing different states:
  • The upper 8 bits: Used to indicate the packet sequence number for internal data updates of the sensor. If the value of this byte increases or changes, it indicates that the sensor output data has been updated.
  • The lower 8 bits: Used to indicate the current status of the sensor, the bits are defined as follows：
    1. Bit0 indicates that the original value is incorrect,
    2. Bit1 indicates that the original value has not been updated for a long time,
    3. Bit2 indicates a trigger timeout.

Due to the limitations of the Modbus-RTU protocol, to obtain complete 32-bit data, it is necessary to read two registers.

Single-point data reading (address range: 4250–4278)

Address	Function Type	Data Format	Data Width
4250	Thumb three-dimensional force Proximity value Tactile state	Normal force(2B) + Tangential force(2B) + Direction angle(2B)+ Proximity value（4B）+ Status value（2B）	6uint16
4256	Index three-dimensional force Proximity value Tactile state	Normal force(2B) + Tangential force(2B) + Direction angle(2B)+ Proximity value（4B）+ Status value（2B）	6uint16
4262	Middle three-dimensional force Proximity value Tactile state	Normal force(2B) + Tangential force(2B) + Direction angle(2B)+ Proximity value（4B）+ Status value（2B）	6uint16
4268	Ring three-dimensional force Proximity value Tactile state	Normal force(2B) + Tangential force(2B) + Direction angle(2B)+ Proximity value（4B）+ Status value（2B）	6uint16
4274	Pinky three-dimensional force Proximity value Tactile state	Normal force(2B) + Tangential force(2B) + Direction angle(2B)+ Proximity value（4B）+ Status value（2B）	6uint16

Raw Touch Channel Value Reading for Five Fingers (Address Range: 4300–4359)

Address	Corresponding Finger	Channel Count	Bytes per Channel	Total Bytes	Description
4300–4311	Thumb	6	4 Bytes	24 Bytes	4 bytes raw value per channel
4312–4323	Index Finger	6	4 Bytes	24 Bytes	4 bytes raw value per channel
4324–4335	Middle Finger	6	4 Bytes	24 Bytes	4 bytes raw value per channel
4336–4347	Ring Finger	6	4 Bytes	24 Bytes	4 bytes raw value per channel
4348–4359	Little Finger	6	4 Bytes	24 Bytes	4 bytes raw value per channel

The tactile channel value is a 32-bit unsigned data.

Tactile Register Description - Piezoresistive

Piezoresistive sensors have 9 sampling points on each finger, distributed from the fingertip to the base of the finger, allowing for a comprehensive perception of tactile feedback on the fingertip surface.

• Data Size per Sampling Point: 2 bytes (16 bits)

• Data Type:
  Raw Value: ADC sampled value, suitable for debugging and internal calibration;
  Calibrated Value: Pressure value converted to physical quantity, measured in g (grams).

• The choice of Data Type can be set via the holding register (0: Raw Value; 1: g value (default)).

• Supported Fingers: Thumb, Index Finger, Middle Finger, Ring Finger, Little Finger

• To facilitate the quick acquisition of the overall force applied to the fingers, the following input registers are added for reading the combined force of the 5 fingers (Raw Value/Calibrated Value):

Register Address	Finger	Description
6001	Thumb	9-point force
6002	Index Finger	9-point force
6003	Middle Finger	9-point force
6004	Ring Finger	9-point force
6005	Pinky Finger	9-point force

Users can read the 9-point pressure values for each finger through the registers and obtain the firmware version string information (10 bytes). Combined with the tactile data switch register control, the module can be started or stopped, saving resources.