HSES Protocol Specification

This skill provides the complete specification for the HSES (High Speed Ethernet Server) protocol used to communicate with Yaskawa robot controllers.

When to Use

Understanding HSES protocol message structure and formats
Implementing or debugging HSES communication
Looking up specific command IDs, attributes, or error codes
Understanding the binary protocol layout (headers, payloads)

Protocol Overview

HSES is a UDP-based communication protocol for Yaskawa robots.

Communication Specifications

Property	Value
Protocol	UDP
Robot Control Port	10040
File Control Port	10041
Endianness	Little-endian

Message Structure

+------------------+
| Header (32 bytes)|
+------------------+
| Payload (≤479B)  |
+------------------+

Header Layout (32 bytes)

Offset	Size	Field	Description
0-3	4	Magic	"YERC"
4-5	2	Header size	Always 0x20 (32)
6-7	2	Payload size	Variable
8	1	Reserved	Always 0x03
9	1	Division	0x01=Robot, 0x02=File
10	1	ACK	0x00=Request, 0x01=Response
11	1	Request ID	Incremental session ID
12-15	4	Block number	See block numbering rules
16-23	8	Reserved	"99999999"
24-31	8	Sub-header	Command-specific

Block Number Rules

Context	Value
Request	Always 0
Single response	0x8000_0000
Multi-response data (not last)	Increment from previous
Multi-response data (last)	Previous + 0x8000_0000
ACK packet	Same as corresponding data

Request Sub-header (bytes 24-31)

Offset	Size	Field
24-25	2	Command ID
26-27	2	Instance
28	1	Attribute
29	1	Service
30-31	2	Padding (0x00)

Response Sub-header (bytes 24-31)

Offset	Size	Field
24	1	Service + 0x80
25	1	Status
26	1	Added status size
27	1	Padding
28-29	2	Added status (error code)
30-31	2	Padding (0x00)

Response Status Values:

0x00: Normal reply
0x08: Command not defined
0x09: Invalid element number
0x1f: Abnormal reply (check added status)
0x28: Instance does not exist

Robot Commands (Division = 0x01)

Command Reference Table

Command ID	Name	Description
0x70	Alarm data reading	Read current alarm
0x71	Alarm history reading	Read alarm history
0x72	Status reading	Read robot status
0x73	Executing job info	Read current job info
0x74	Axis configuration	Read axis config
0x75	Position data reading	Read robot position
0x76	Position error reading	Read position error
0x77	Torque data reading	Read torque data
0x78	I/O data	Read/write I/O
0x79	Register data	Read/write registers
0x7A	Byte variable (B)	8-bit unsigned
0x7B	Integer variable (I)	16-bit signed
0x7C	Double variable (D)	32-bit signed
0x7D	Real variable (R)	32-bit float
0x7E	String variable (S)	16-byte string
0x7F	Position variable (P)	Robot position
0x80	Base position (BP)	Base position
0x81	External axis (EX)	External axis
0x82	Alarm reset	Reset/cancel alarms
0x83	HOLD/Servo control	HOLD and servo ON/OFF
0x84	Cycle mode switch	Step/cycle/continuous
0x85	PP message display	Show message on pendant
0x86	Job START	Start job execution
0x87	Job select	Select job
0x88	Management time	Get management time
0x89	System information	Get system info
0x8A	Move (Cartesian)	Move command
0x8B	Move (Pulse)	Move command
0x8C	String (S) 32-byte	32-byte string variable
0x300	Plural I/O	Multiple I/O
0x301	Plural register	Multiple registers
0x302	Plural B variable	Multiple byte vars
0x303	Plural I variable	Multiple integer vars
0x304	Plural D variable	Multiple double vars
0x305	Plural R variable	Multiple real vars
0x306	Plural S variable	Multiple string vars
0x307	Plural P variable	Multiple position vars
0x308	Plural BP variable	Multiple base pos vars
0x309	Plural EX variable	Multiple ext axis vars
0x30A	Alarm data (sub code)	Alarm with sub strings
0x30B	Alarm history (sub)	History with sub strings
0x30C	Plural S 32-byte	Multiple 32-byte strings
0x0411	Encoder temperature	Read encoder temp
0x0413	Converter temperature	Read converter temp

Service Types

Service	Value	Description
Get_Attribute_Single	0x0E	Read single attribute
Get_Attribute_All	0x01	Read all attributes
Set_Attribute_Single	0x10	Write single attribute
Set_Attribute_All	0x02	Write all attributes

File Commands (Division = 0x02)

File commands use Command ID = 0x00 and are distinguished by Service code.

Service	Name	Direction	Description
0x09	File delete	-	Delete file on controller
0x15	File loading	PC → FS100	Upload file to controller
0x16	File saving	FS100 → PC	Download file from controller
0x32	File list	FS100 → PC	Get directory listing

File Transfer Protocol

Downloading file from controller (File Saving, Service 0x16):

Send request with filename
Receive file data blocks from controller
Send ACK for each data block
Continue until final block (bit 31 set in block number)

Uploading file to controller (File Loading, Service 0x15):

Send request with filename
Receive ACK for command acceptance
Send file data blocks to controller
Receive ACK for each data block
Set bit 31 on final block

Status Data Structure

Status Data 1 (Command 0x72, Instance 1)

Bit	Meaning when ON
0	Step mode
1	One-cycle mode
2	Continuous mode
3	Running
4	Speed limited
5	Teach mode
6	Play mode
7	Remote mode
8-15	Reserved

Status Data 2 (Command 0x72, Instance 2)

Bit	Meaning when ON
0	Hold pending
1	Hold by external
2	Hold by command
3	Servo ON (ready)
4	Error
5	Alarm
6-15	Reserved

Common Error Codes (Added Status)

Code	Meaning
0x1010	Cannot operate (mode/state)
0x1018	Servo not ready
0x2010	Cannot operate in teach mode
0x2050	In hold state
0x2060	System already in requested state
0x3040	Job not found
0x3400	File not found
0x4040	Invalid variable index

Related Skills

For implementing HSES communication in Rust, see:

moto-hses-usage: Client library usage guide for the moto-hses crate family

Detailed Reference

For complete protocol details including all command payloads, response formats, and example packets, see:

references/protocol-overview.md - Protocol structure and header format
references/sequence-diagrams.md - Communication flow diagrams
references/robot-commands-status.md - Status and alarm commands
references/robot-commands-variables.md - Variable read/write commands
references/robot-commands-control.md - Control and motion commands
references/file-commands.md - File operation commands
references/data-types.md - Variable types and position formats
references/error-codes.md - Error code definitions

hses-protocol