Troubleshooting ECR Integration

Overview

This guide helps developers troubleshoot issues encountered during the Electronic Cash Register (ECR) integration with Maya Terminals.

It covers setup, communication, and application-level errors across the following components in ECR integration:

• ECR
• ECR Plugin
• Maya Terminal
• ECR App
• ONE App

Each issue includes a description, possible causes, impacts, and step-by-step resolutions to help you identify and fix problems efficiently.

---

ECR Errors

These are setup or configuration issues that occur on the ECR side, before communication with the Maya Terminal is established.

Maya Terminal Not Detected or Not Showing in COM Port List

Symptoms:

The terminal is not detected or does not appear under COM ports in the Device Manager.

Possible Cause/s:

• The terminal is not powered on or is not connected properly
• Faulty USB cable or port
• Missing, corrupted, or incorrect USB driver
• COM port not detected or changing frequently
• Baud rate mismatch
• Outdated firmware or Maya Applications

Impact:

Communication cannot begin between the ECR and the terminal.

Troubleshooting Steps:

1. Check Physical Connection
   • Ensure the terminal is securely connected
   • Try a different USB port
   • Use an alternative cable (PAX: Micro USB; SUNMI: Type-C)
2. Check Driver Installation
   • If no COM port appears, install or reinstall the driver manually, refer to ECR Integration Setup
   • For SUNMI Terminal not detected or not showing in the COM Port List:
     • During driver installation, temporarily disable your firewall or antivirus.
     • If disabling security software is not possible, whitelist the SUNMI terminal driver within your OS or antivirus configuration.
     • Once the driver installation completes successfully, re-enable your firewall and antivirus to maintain security.
     • Reconnect the terminal and verify that it appears under the correct COM port list. Example path (Windows): Device Manager → Ports (COM & LPT)
     • If it still shows as Unknown Device, uninstall the device driver, reconnect the terminal, and reinstall the driver as Administrator.
3. Verify COM Port
   • To verify the COM Port, follow the Preparation for ECR Integration
   • Confirm the port appears when the device is connected
   • Note the COM number (e.g., COM11)
4. Fix Port Assignment
   • If the COM number changes after reconnection, assign a fixed COM port to prevent communication errors.
5. Align the Baud Rate
   • Verify the baud rate settings on both the ECR Plugin in the ECR and the ECR App in the Terminal.
   • Ensure both are set to the same value (e.g., 9600 or 115200)
   • Save and restart both systems
6. Initialize the ECR Application
   • Open the Maya ECR application on the terminal.
   • Wait approximately 1 minute to allow the ECR App Service to fully initialize after startup.
   • Once initialized, the terminal should now be visible in the COM port list and ready to receive commands from the host computer.

Unable to Open Port

Symptoms:

The ECR system cannot establish communication with the terminal via the configured COM port.

Possible Cause/s:

• Incorrect COM port selection or the port is already in use by another process.
• USB driver is missing, corrupted, or not installed automatically.

Impact:

The ECR cannot send or receive transaction data.

Troubleshooting Steps:

1. Check Physical Connection
   • Ensure the terminal is securely connected
   • Try a different USB port
   • Use an alternative cable (PAX: Micro USB; SUNMI: Type-C)
2. Check Driver Installation
   • If no COM port appears, install or reinstall the driver manually, refer to ECR Integration Setup
3. Verify COM Port
   • To verify the COM Port, follow the Preparation for ECR Integration
   • Confirm the port appears when the device is connected
   • Note the COM number (e.g., COM11)
4. Fix Port Assignment
   • If the COM number changes after reconnection, assign a fixed COM port to prevent communication errors.
5. Initialize the ECR Application
   • Open the Maya ECR application on the terminal.
   • Wait approximately 1 minute to allow the ECR App Service to fully initialize after startup.
   • Once initialized, the terminal should now be visible in the COM port list and ready to receive commands from the host computer.

---

Maya ECR App Errors

These occur within the Maya Terminal, typically involving the ECR App.

E:0001 - ECR Application Not Yet Configured

Description: The ECR application is not configured to connect to the base.

Cause and Impact: Occurs during first-time setup or when the base has not yet been paired, resulting in communication failure between the terminal and the base.

Resolution:

• Scan the barcode on the A920 terminal to pair it with the base.
• If already paired, restart the ECR application and try again.

E:0002 - Payment Application Not Found

Description: The required payment application (Maya ONE App) is missing or not properly installed.

Cause and Impact: The ECR app depends on the Maya ONE App for payment transactions. Without it, payment requests cannot be processed.

Resolution:

• Go to Settings → Apps on the device to verify if the Maya ONE App is installed.
• If not present, contact Maya Support to assist with installation.

E:0003 - Error Connecting to USB/L920 Base

Description: The ECR App cannot detect the L920 base or USB link.

Cause and Impact: A cable is disconnected or the base is not powered, resulting in a connection interruption.

Resolution:

• Ensure the USB cable is properly connected.
• Confirm the L920 base is powered on.
• Check if the A920 is charging when docked.

E:9002 - ECR Initialization Error

Description: General error during ECR App startup or background service.

Cause and Impact: The app failed to initialize due to temporary service errors, such as the application background service experiencing an error

Resolution: Restart the application and try again.

---

Tips for Developers

• Always test connections before production.
• Maintain consistent COM port and baud rate settings across all configurations.
• Capture logs from the ECR Plugin and ECR App for root cause analysis.
• For recurring USB/COM issues, verify if the ECR driver auto-launches on boot.

---

FAQs

Q: Why does the COM port change after reconnecting the device?

A: Windows dynamically assigns new COM ports. Set a static COM assignment to prevent configuration mismatches.

Q: Can I use a USB hub to connect multiple terminals?

A: It’s not recommended. Direct USB connection ensures stable data transmission.

---

Next Steps

Now that you’ve learned the most common troubleshooting procedures:

• Keep your ECR and Maya applications regularly updated to prevent compatibility and version-related issues.
• Review and apply Handling Timeouts in ECR-Integrated Terminals [link]
• Validate your setup Using the ECR Simulator Tool