Error Codes

Error Codes Reference

This document provides a comprehensive reference for error codes across FlashForge API interfaces.

HTTP API Error Codes

The HTTP REST API (port 8898) uses a standard JSON response envelope for all endpoints.

Response Format

Success:

{
  "code": 0,
  "message": "Success"
}

Error:

{
  "code": <non-zero>,
  "message": "Error description"
}

HTTP API Code Reference

Code	Message	Description
0	Success	Operation completed successfully
1	Error	Generic error occurred
2	Invalid parameter	Request payload contains invalid parameters
3	Unauthorized	Authentication failed (invalid serial or check code)
4	Not found	Requested resource or file not found
5	Busy	Printer is busy with another operation

Handling Notes

• Clients should check code === 0 for success rather than parsing the message string
• Message case may vary ("Success" vs "success") between firmware versions
• Error descriptions in the message field may provide additional context

Common Error Scenarios

Code 3 - Unauthorized

Causes:

• Invalid serialNumber
• Invalid checkCode
• Check code has been changed on the printer

Resolution: Verify credentials in printer settings menu.

Code 4 - Not Found

Causes:

• Requested file does not exist in /printGcode
• Invalid endpoint path

Resolution: Use /gcodeList to verify available files.

Code 5 - Busy

Causes:

• Another operation is in progress
• Printer is performing internal task

Resolution: Wait and retry the operation.

IFS Error Codes (AD5X Only)

These errors appear in /detail responses or blocking dialogs when using the Material Station (Intelligent Filament System).

Feeding Errors

Code	Description	Trigger
E0100	Channel 1 feeding timeout	Load failure (Slot 1)
E0101	Channel 2 feeding timeout	Load failure (Slot 2)
E0102	Channel 3 feeding timeout	Load failure (Slot 3)
E0103	Channel 4 feeding timeout	Load failure (Slot 4)

Retraction Errors

Code	Description	Trigger
E0104	Channel 1 retracting timeout	Unload failure (Slot 1)
E0105	Channel 2 retracting timeout	Unload failure (Slot 2)
E0106	Channel 3 retracting timeout	Unload failure (Slot 3)
E0107	Channel 4 retracting timeout	Unload failure (Slot 4)

System Errors

Code	Description	Trigger
E0108	Feed failure to extruder	Filament sensor timeout during feed
E0109	Odometer stall	Filament tangle or jam (stall count > 200)
E0114	IFS homing error	Selector mechanism failure

TCP Protocol Errors

Legacy TCP commands (port 8899) return plain text error messages.

Session Errors

Error Message	Description
Control Failed	Another client is connected or previous session not closed
CMD M601 Received. Control Failed.	Session request rejected
Error: have been connected	Session already active (M601)

Resolution: Wait for existing session to timeout or ensure M602 was sent before reconnecting.

File Upload Errors

Error Message	Description
Error: Not enough space	Insufficient storage for file upload (M28)
Error: File Is Not Available	File size mismatch during upload (M29)

Resolution:

• "Not enough space": Delete files from printer storage
• "File Is Not Available": Verify file size matches M28 parameter, retransmit file

Command Errors

Error Message	Description
Error: Invalid command	Unknown or malformed command

Detail Response Error Fields

The /detail endpoint may include error information in the response:

{
  "detail": {
    "errorCode": "E0100",
    "status": "error"
  }
}

Checking for Errors

1. Check status field for value "error"
2. Inspect errorCode field for specific error code
3. Cross-reference with error tables above

Error Recovery Strategies

HTTP API Errors

Code	Strategy
1	Retry operation, check printer state
2	Validate request payload format
3	Re-authenticate with correct credentials
4	Verify resource exists before requesting
5	Poll /detail until status changes from "busy"

TCP Errors

Error	Strategy
Control Failed	Wait 30 seconds and retry connection
Not enough space	Use HTTP /gcodeList to identify and remove files
File Is Not Available	Verify file integrity, retransmit

IFS Errors

Strategy	Implementation
Poll status	Check matlStationInfo.stateAction during operations
Retry with backoff	Implement exponential backoff for transient errors
User notification	Display actionable error messages to users
Recovery commands	Use ms_cmd with action "cancel" to abort failed operations

Best Practices

Error Handling

1. Always check response code field, not just HTTP status
2. Implement retry logic with exponential backoff for codes 1 and 5
3. Log error codes for debugging and support
4. Display user-friendly messages based on error context

Timeout Handling

For long-running operations:

• Use appropriate timeouts (30-60 seconds for most operations)
• Implement progress polling for file uploads
• Handle network disconnections gracefully

IFS-Specific Handling

For AD5X material station operations:

1. Check matlStationInfo.stateAction before starting operations
2. Monitor state during multi-step operations
3. Implement error recovery workflows
4. Clear errors using errorCodeCtrl_cmd if available