LattePanda Delta 3 Controller

What It Is

The LattePanda Delta 3 is a single-board computer used as an I/O controller at the Teasdale Carrollton site. It performs the same function as the Arduino Portenta H7 -- controlling stack lights, reject signals, and other conveyor outputs -- but connects via serial USB instead of TCP/IP.

Which Sites Use It

• Teasdale Carrollton (Line 7 and Line 9)

Connection Details

Detail	Value
Protocol	Serial USB
Default baud rate	115200
Connection string format	COMx:BAUDRATE (e.g., COM4:115200)
Communication	JSON commands and responses (same as Arduino Portenta)

How to Tell If It Is Working

1. Diagnostics panel: Controller shows "Connected" with a green indicator.
2. Stack light test: Use the diagnostics panel stack light buttons.
3. COM port check: Verify the COM port is listed in Windows Device Manager under "Ports (COM & LPT)."
4. Log on startup: Check for successful serial connection and sendStatus response.

Common Problems and Solutions

Problem	Symptoms	Solution
Controller not connecting	Log shows "Serial port {COMx} not found"	Check USB cable, verify COM port in Device Manager
COM port in use	Log shows "Access denied to serial port {COMx}"	Close other applications using the port (terminal programs, etc.)
No status response	Log shows "Serial port opened but Arduino did not respond to 'sendStatus' command"	Check firmware, try power cycling the LattePanda
Connection drops	Log shows "Serial port closed during monitoring"	USB cable loose, try different USB port
Stack lights not responding	No light changes on test	Check wiring, verify pin assignments

Error Messages

Error Message	What It Means
Access denied to serial port {COMx}. Port may be in use by another application.	Another program has the COM port open
Serial port {COMx} not found or could not be opened. Check COM port number and USB connection.	COM port does not exist -- USB cable disconnected or wrong port number
Serial port opened but Arduino did not respond to 'sendStatus' command.	Connected but controller is not responding
Cannot send Serial command - not connected	Serial connection is down
Serial port closed during monitoring	USB connection lost during operation
No valid JSON found in TCP response	Controller returned unexpected data

COM Port Identification

If you are unsure which COM port the LattePanda is on: 1. Open Device Manager on the GateKeeper PC. 2. Expand Ports (COM & LPT). 3. Look for a USB serial device -- note the COM number. 4. If unsure, disconnect the LattePanda USB cable and see which entry disappears.

Differences from Arduino Portenta

The LattePanda uses the same JSON command protocol as the Arduino Portenta H7. The only difference is the connection type:

Aspect	Arduino Portenta H7	LattePanda Delta 3
Connection	TCP/IP (network)	Serial USB (COM port)
Connection string	IP:PORT	COMx:BAUDRATE
Sites	Cargill, Hormel	Teasdale

All output commands (stack lights, reject, stop, horn) work identically regardless of which controller is used.

When to Escalate

• COM port not appearing in Device Manager (driver or hardware issue)
• Controller responds to sendStatus but outputs do not work (wiring or firmware issue)
• Persistent USB disconnections despite good cable and port