Lingxi Gloria-D Series Servo Communication Protocol Manual

1. Overview

This document applies to the servo communication control of the Lingxi Gloria-D Series robotic arms.

2. Communication Protocol Specification

2.1 Basic Communication Parameters

Parameter	Value
Baud Rate	1000000 bps (default)
Data Bits	8 bits
Stop Bits	1 bit
Parity	None
Communication	Half-duplex UART

2.2 Packet Format

The communication packet uses the following format:

Header (2 bytes: 0xFF, 0xFF) + ID (1 byte) + Length (1 byte) + Instruction (1 byte) + Parameters (N bytes) + Checksum (1 byte)

Field	Description
Header	Fixed as two bytes 0xFF, 0xFF
ID	Servo ID (0-254, 0xFE is the broadcast ID)
Length	Parameter length + 3 (Instruction + Checksum)
Instruction	Command type
Parameters	Command parameters
Checksum	Checksum

2.3 Checksum Calculation

Checksum calculation formula:

Checksum = ~(ID + Length + Instruction + Parameter1 + ... + ParameterN) & 0xFF

3. Main Command Descriptions

3.1 PING Instruction

Function: Test whether the servo is connected properly

Instruction Format:

Header	ID	Length	Instruction	Checksum
0xFF, 0xFF	ID	0x02	0x01	Checksum

Response:

Header	ID	Length	Error	Checksum
0xFF, 0xFF	ID	0x02	Error	Checksum

3.2 READ Instruction

Function: Read servo data

Instruction Format:

Header	ID	Length	Instruction	Address	Length	Checksum
0xFF, 0xFF	ID	0x04	0x02	Address	Length	Checksum

Parameter Description:

• Address: Read start address
• Length: Length of data to read

3.3 WRITE Instruction

Function: Write data to the servo

Instruction Format:

Header	ID	Length	Instruction	Address	Data1	Data2	...	Checksum
0xFF, 0xFF	ID	Length	0x03	Address	Data	Data	...	Checksum

3.4 REG WRITE Instruction

Function: Write data and wait for the ACTION instruction to execute

Instruction Format:

Header	ID	Length	Instruction	Address	Data1	Data2	...	Checksum
0xFF, 0xFF	ID	Length	0x04	Address	Data	Data	...	Checksum

3.5 ACTION Instruction

Function: Trigger the previously written action

Instruction Format:

Header	ID	Length	Instruction	Checksum
0xFF, 0xFF	ID	0x02	0x05	Checksum

3.6 RESET Instruction

Function: Reset servo settings

Instruction Format:

Header	ID	Length	Instruction	Checksum
0xFF, 0xFF	ID	0x02	0x06	Checksum

4. Control Table Description

4.1 Basic Information Area (Address 0-23)

Address	Name	Description	Length	Access
0	Model Number L	Model number low byte	1	Read-only
1	Model Number H	Model number high byte	1	Read-only
2	Version	Firmware version	1	Read-only
3	ID	Servo ID	1	Read/Write
4	Baud Rate	Baud rate	1	Read/Write
5	Return Delay Time	Return delay time	1	Read/Write
6	CW Angle Limit L	Clockwise angle limit low byte	1	Read/Write
7	CW Angle Limit H	Clockwise angle limit high byte	1	Read/Write
8	CCW Angle Limit L	Counterclockwise angle limit low byte	1	Read/Write
9	CCW Angle Limit H	Counterclockwise angle limit high byte	1	Read/Write
10	System Data2	System data 2	1	Read-only
11	Limit Temperature	Maximum temperature limit	1	Read/Write
12	Down Limit Voltage	Minimum voltage limit	1	Read/Write
13	Up Limit Voltage	Maximum voltage limit	1	Read/Write
14	Max Torque L	Maximum torque low byte	1	Read/Write
15	Max Torque H	Maximum torque high byte	1	Read/Write
16	Return Level	Return status level	1	Read/Write
17	Alarm LED	LED alarm	1	Read/Write
18	Alarm Shutdown	Shutdown alarm	1	Read/Write
19	Operating Mode	Operating mode	1	Read/Write
20	Down Calibration L	Lower-limit calibration low byte	1	Read/Write
21	Down Calibration H	Lower-limit calibration high byte	1	Read/Write
22	Up Calibration L	Upper-limit calibration low byte	1	Read/Write
23	Up Calibration H	Upper-limit calibration high byte	1	Read/Write

4.2 Status Information Area (Address 24-35)

Address	Name	Description	Length	Access
24	Torque Enable	Torque enable	1	Read/Write
25	LED	LED status	1	Read/Write
26	CW Compliance Margin	Clockwise compliance margin	1	Read/Write
27	CCW Compliance Margin	Counterclockwise compliance margin	1	Read/Write
28	CW Compliance Slope	Clockwise compliance slope	1	Read/Write
29	CCW Compliance Slope	Counterclockwise compliance slope	1	Read/Write
30	Goal Position L	Goal position low byte	1	Read/Write
31	Goal Position H	Goal position high byte	1	Read/Write
32	Moving Speed L	Moving speed low byte	1	Read/Write
33	Moving Speed H	Moving speed high byte	1	Read/Write
34	Torque Limit L	Torque limit low byte	1	Read/Write
35	Torque Limit H	Torque limit high byte	1	Read/Write

4.3 Feedback Information Area (Address 36-49)

Address	Name	Description	Length	Access
36	Present Position L	Current position low byte	1	Read-only
37	Present Position H	Current position high byte	1	Read-only
38	Present Speed L	Current speed low byte	1	Read-only
39	Present Speed H	Current speed high byte	1	Read-only
40	Present Load L	Current load low byte	1	Read-only
41	Present Load H	Current load high byte	1	Read-only
42	Present Voltage	Current voltage	1	Read-only
43	Present Temperature	Current temperature	1	Read-only
44	Registered Instruction	Registered instruction	1	Read-only
45	Reserved	Reserved	1	Read-only
46	Moving	Moving status	1	Read-only
47	Lock	Lock	1	Read-only
48	Punch L	Punch low byte	1	Read/Write
49	Punch H	Punch high byte	1	Read/Write

5. Angle and Position Conversion

5.1 Angle Range

• Minimum Angle: 0°
• Maximum Angle: 300° (depending on the specific model)
• Resolution: 0.29°

5.2 Position Value Calculation

Position value range: 0 - 1023

Angle to Position Value:

Position = (Angle / 300) * 1023

Position Value to Angle:

Angle = (Position / 1023) * 300

6. Complete Example: Angle Control and Angle Feedback for Each Servo of the Robotic Arm

Please refer to the following complete protocol in detail and familiarize yourself with the meaning of each part:

1. Header Default is 0xFF, 0xFF: | 0xFF | 0xFF | 0x01 | 0x02 | 0x01 | 0xFB |

2. Instruction ID 0x01, executes the PING instruction: | 0xFF | 0xFF | 0x01 | 0x02 | 0x01 | 0xFB |

3. Instruction Length 0x02, indicates the instruction length is 2 bytes: | 0xFF | 0xFF | 0x01 | 0x02 | 0x01 | 0xFB |

4. Instruction Type 0x01, PING instruction: | 0xFF | 0xFF | 0x01 | 0x02 | 0x01 | 0xFB |

5. Checksum 0xFB, checksum calculation: | 0xFF | 0xFF | 0x01 | 0x02 | 0x01 | 0xFB |

6. Response Frame | 0xFF | 0xFF | 0x01 | 0x02 | 0x00 | 0xFB |

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7. Complete Example: Reading the Current Servo Position

Please refer to the following complete protocol in detail and familiarize yourself with the meaning of each part:

1. Header Default is 0xFF, 0xFF: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

2. Instruction ID 0x01, executes the READ instruction: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

3. Instruction Length 0x04, indicates the parameter length is 4 bytes: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

4. Instruction Type 0x02, READ instruction: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

5. Parameter 0x24, read start address (current position): | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

6. Read Length 0x02, read 2 bytes: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

7. Checksum 0xD9, checksum calculation: | 0xFF | 0xFF | 0x01 | 0x04 | 0x02 | 0x24 | 0x02 | 0xD9 |

8. Response Frame Example | 0xFF | 0xFF | 0x01 | 0x04 | 0x00 | 0xE8 | 0x03 | 0x16 |

9. Response Parsing

   • 0xFF, 0xFF: Header
   • 0x01: Servo ID
   • 0x04: Data length
   • 0x00: Error code (no error)
   • 0xE8: Position low byte
   • 0x03: Position high byte
   • 0x16: Checksum

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8. Error Codes

Error Value	Meaning
0	No error
1	Input voltage error
2	Angle limit error
4	Overheating error
8	Angle range error
16	Overload error
32	Instruction error
64	Checksum error

9. Notes

1. Communication Timing: There should be at least a 1 ms interval between two adjacent packets
2. Servo ID: It is recommended to use an ID between 1 and 253; avoid using the broadcast ID (0xFE) for write operations
3. Baud Rate Setting: The servo must be restarted after changing the baud rate
4. Temperature Monitoring: Monitor the servo temperature during prolonged operation
5. Load Limit: Ensure the servo load does not exceed the rated value
6. Firmware Upgrade: Periodically check and upgrade the servo firmware

10. Troubleshooting

Common Issues:

1. Communication failure: Check the baud rate, servo ID, and connection cables
2. Servo not responding: Check the power supply voltage and whether the servo is locked
3. Inaccurate position: Check the angle limit settings and calibration parameters
4. Overheat protection: Reduce the load and improve heat dissipation