Modbus Error Codes
| Error code (Decimal) |
Error code (Hex) |
Meaning |
|---|---|---|
| 0 | 0x000 | No Error |
| 1 | 0x001 | Illegal Buffer Length |
| 3 | 0x003 | Invalid Command |
| 5 | 0x005 | Timeout |
| 6 | 0x006 | Receive Buffer Too Small |
| 8 | 0x008 | Invalid Local Session Number in NCB LSN |
| 9 | 0x009 | Out of Resources |
| 10 | 0x00A | Session Closed |
| 11 | 0x00B | Command Cancelled |
| 13 | 0x00D | Duplicate Local Name |
| 14 | 0x00E | Local Name Table is Full |
| 15 | 0x00F | Close Command was Issued But Sessions Still Active |
| 17 | 0x011 | Local Session Table is Full |
| 18 | 0x012 | Routing Failure, Remote Node Not Responding |
| 19 | 0x013 | Invalid Name - Bad Value in NCB NUM |
| 20 | 0x014 | Name Not Found |
| 21 | 0x015 | Invalid Name - No Entry in Local Name Table |
| 22 | 0x016 | Name Already Exists on Network |
| 23 | 0x017 | Name was Deleted |
| 24 | 0x018 | Session Abnormally Terminated |
| 25 | 0x019 | Name Conflict - Two Nodes Using the Same Name Detected |
| 33 | 0x021 | Adapter Busy - Command Cannot Execute |
| 34 | 0x022 | Too Many Commands Queued |
| 35 | 0x023 | Invalid Values for NCB LANA NUM - Must be 0 or 1 |
| 36 | 0x024 | Command Completed Before Cancel Issued |
| 38 | 0x026 | Invalid Cancel Command - Target NCB Cannot be Found |
| 78 | 0x04E | Hardware Error Code |
| 255 | 0x0FF | Still Processing Command |
| 256 | 0x100 | Writing Invalid Data |
| 257 | 0x101 | Illegal Function for the Addressed Slave |
| 258 | 0x102 | Illegal Data Address in the Information Fields for the Addressed Slave |
| 259 | 0x103 | Illegal Data Value in the Information Fields for the Addressed Slave |
| 260 | 0x104 | Failure in Associated Device |
| 261 | 0x105 | Acknowledge - Processing Programming Command |
| 262 | 0x106 | Busy - Reissue Command Later |
| 263 | 0x107 | Negative Acknowledge - cannot perform program function |
| 264 | 0x108 | Memory Parity Error |
| 266 | 0x10A | Gateway Path Unavailable |
| 267 | 0x10B | Gateway Target Device Failed to Respond |
| 512 | 0x200 | Illegal Memory Address in Read |
| 513 | 0x201 | Illegal Memory Address in Write |
| 514 | 0x202 | Error Loading NETLIB.DLL |
| 515 | 0x203 | Error Opening Serial Port |
| 516 | 0x204 | Timed Out Waiting for Echoed Message |
| 517 | 0x205 | Timed Out Waiting for Response from Remote |
| 518 | 0x206 | Received Message CRC Error |
| 519 | 0x207 | Unknown Error |
| 520 | 0x208 | Attempting to Write Invalid Data to PLC |
| 521 | 0x209 | Attempting to Send Invalid Read Msg to PLC |
| 528 | 0x210 | No Path Available for Message |
| 529 | 0x211 | Command Mismatch |
| 530 | 0x212 | Response from Wrong Station |
| 531 | 0x213 | Communication Channel Not Available |
| 532 | 0x214 | Send/Receive Out of Sync |
| 533 | 0x215 | Response from wrong data logger |
| 534 | 0x216 | Corrupt or illegal MODBUS/TCP header |
| 535 | 0x217 | Illegal value in response |
| 536 | 0x218 | Purge of data log records failed |
| 537 | 0x219 | Session Open Illegal Command |
| 538 | 0x21A | Session Open Illegal Version |
| 546 | 0x222 | Unknown Modbus Exception Code Returned |
| 551 | 0x227 | Bad Transport Mode |
| 768 | 0x300 | No Error |
| 769 | 0x301 | Port Not Defined |
| 770 | 0x302 | Port Failed To Connect |
| 771 | 0x303 | Port Lost Connection |
| 772 | 0x304 | Serial Port Settings Out of Range |
| 773 | 0x305 | Serial Port Already In Use or Not Available |
| 774 | 0x306 | Serial Port Access Denied |
| 775 | 0x307 | Serial Port General Failure |
| 776 | 0x308 | Serial Port Invalid Parameter |
| 777 | 0x309 | Port Not Connected |
| 784 | 0x310 | Port Unknown Error |
