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Error Reference: Connection Errors

This page lists hardware connection error messages, grouped by device type.


Camera Errors (Cognex DataMan / Insight)

"Failed to connect to Cognex camera at {IP}:{Port}"

  • What it means: The application could not establish a TCP connection to the camera.
  • Common causes: 1. Camera is powered off. 2. Wrong IP address or port in appsettings.json. 3. Network cable disconnected. 4. Firewall blocking port 23.
  • Resolution: 1. Verify the camera is powered on. 2. Ping the camera IP. 3. Check the Ethernet cable. 4. Verify IP and port in appsettings.json HardwareSettings section.
  • When to escalate: If the camera is reachable by ping but the application still cannot connect.

"Cannot trigger camera - not connected"

  • What it means: A validation attempt tried to trigger the camera, but the camera is currently disconnected.
  • Common causes: Camera lost connection after startup.
  • Resolution: Check the camera connection. The application will attempt automatic reconnection.

"No response from camera after trigger"

  • What it means: The camera was triggered but did not respond within the timeout period.
  • Common causes: 1. Camera is busy or frozen. 2. Network congestion. 3. Camera firmware issue.
  • Resolution: 1. Wait for the next trigger (the camera may recover). 2. If it persists, restart the application. 3. Power-cycle the camera if necessary.

"Connection error during camera trigger - attempting reconnection"

  • What it means: The network connection to the camera was lost during a trigger operation. The application is automatically trying to reconnect.
  • Common causes: 1. Network cable was briefly disconnected. 2. Camera was power-cycled. 3. Network switch glitch.
  • Resolution: Usually resolves automatically. If reconnection fails, restart the application.

"Failed to reconnect to camera - trigger aborted"

  • What it means: The automatic reconnection attempt to the camera failed.
  • Common causes: Camera is powered off or unreachable.
  • Resolution: Verify camera power and network connection, then restart the application.

"Barcode line has unexpected format (expected 6 CSV fields): {line}"

  • What it means: The camera sent data in an unexpected format.
  • Common causes: Camera firmware or configuration was changed.
  • Resolution: Check camera configuration. This may require development team involvement.
  • When to escalate: Always -- camera data format mismatch is a configuration or firmware issue.

Camera Errors (Zebra DS9908R)

"[DS9908] Failed to open CoreScanner. Status: {status}"

  • What it means: The Zebra CoreScanner SDK could not be initialized.
  • Common causes: 1. CoreScanner service is not running. 2. CoreScanner SDK is not installed. 3. Another application is using the CoreScanner.
  • Resolution: 1. Open Windows Services and ensure Zebra CoreScanner service is running. 2. Restart the CoreScanner service. 3. If not installed, reinstall from the SDK package.

"[DS9908] No scanners discovered, but staying connected for hot-plug"

  • What it means: The CoreScanner SDK is running but no physical scanner was found on USB.
  • Common causes: 1. Scanner USB cable is disconnected. 2. Scanner is powered off. 3. Wrong USB port.
  • Resolution: 1. Check the USB cable connection. 2. Try a different USB port. 3. The application will automatically detect the scanner when it is plugged in.

"[DS9908] Cannot trigger - not connected"

  • What it means: A scan was requested but the scanner is not connected.
  • Common causes: Scanner USB cable disconnected during operation.
  • Resolution: Reconnect the USB cable.

"[DS9908] Software trigger failed. Status: {status}"

  • What it means: The command to trigger a scan failed.
  • Common causes: Scanner firmware issue or communication error.
  • Resolution: Restart the application. If it persists, power-cycle the scanner.
  • When to escalate: If the error persists after restart.

RFID Reader Errors (Zebra FX9600)

"Connection failed: {result}. {message}"

  • What it means: The application could not connect to the RFID reader.
  • Common causes: 1. RFID reader is powered off. 2. Wrong IP address in appsettings.json. 3. Port 5084 is blocked. 4. Network cable disconnected.
  • Resolution: 1. Verify reader is powered on. 2. Ping the reader IP. 3. Check port 5084 is open. 4. Check Ethernet cable.

"Not connected to reader."

  • What it means: An operation was attempted on the RFID reader, but it is not connected.
  • Common causes: Reader connection was lost.
  • Resolution: Check the RFID reader connection and restart the application.

"Reader disconnected unexpectedly."

  • What it means: The RFID reader lost connection while in operation.
  • Common causes: 1. Network interruption. 2. Reader was power-cycled. 3. Ethernet cable issue.
  • Resolution: Check the reader and network, then restart the application.

"Buffer full - consider reading tags faster."

  • What it means: The RFID reader's internal tag buffer is full.
  • Common causes: Too many RFID tags in the read zone at once.
  • Resolution: This is informational. Reduce the number of tags in the read zone or increase the read rate.

"Antenna {id} connected/disconnected."

  • What it means: An RFID antenna was physically connected or disconnected.
  • Common causes: Antenna cable was moved or disconnected.
  • Resolution: Check the antenna cable connection to the reader.

Arduino / Controller Errors

"Socket error connecting to Arduino Portenta at {IP}:{Port}"

  • What it means: The TCP connection to the Portenta H7 controller failed.
  • Common causes: 1. Controller is powered off. 2. Wrong IP or port. 3. Network cable disconnected.
  • Resolution: Check power, Ethernet cable, and IP/port configuration.

"TCP connection established but Arduino did not respond to 'sendStatus' command."

  • What it means: The network connection was made, but the Arduino firmware did not respond to the verification command.
  • Common causes: 1. Arduino firmware is not running. 2. Wrong firmware version. 3. Arduino is frozen.
  • Resolution: Power-cycle the Arduino. If it persists, the firmware may need to be updated.
  • When to escalate: If the Arduino does not respond after power-cycling.

"Access denied to serial port {ComPort}. Port may be in use by another application."

  • What it means: The serial COM port is in use by another program.
  • Common causes: 1. Another instance of GateKeeper is running. 2. A serial terminal (PuTTY, etc.) is connected to the port. 3. Another application is using the port.
  • Resolution: Close the other application using the COM port and restart GateKeeper.

"Serial port {ComPort} not found or could not be opened."

  • What it means: The configured COM port does not exist on this machine.
  • Common causes: 1. USB cable disconnected. 2. COM port number changed. 3. USB driver not installed.
  • Resolution: 1. Check the USB cable. 2. Open Device Manager and find the current COM port number. 3. Update appsettings.json with the correct COM port.

"Cannot control stack light - Arduino not connected"

  • What it means: A stack light command was sent but the controller is disconnected.
  • Common causes: Controller lost connection.
  • Resolution: Check the controller connection and restart the application.

"Cannot send reject signal - Arduino not connected"

  • What it means: A reject signal was attempted but the controller is disconnected. Cases will not be physically rejected.
  • Common causes: Controller lost connection during operation.
  • Resolution: Reconnect the controller immediately -- the line may need to be stopped if reject signals are critical.

"TCP connection lost during monitoring" / "Serial port closed during monitoring"

  • What it means: The connection to the controller was lost during normal operation.
  • Common causes: 1. Cable disconnected. 2. Controller power loss. 3. USB glitch (serial).
  • Resolution: Check the cable and power, then restart the application.