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WB-MGE v.3 known issues

revision 107707

ERRWB-MGEv30001: Device reboots when a USB-C cable is connected or disconnected

Affected devices

All WB-MGE v.3 devices.

Description

The device reboots when a USB-C cable is connected or disconnected.

Cause and details

A USB-UART converter provides convenient USB flashing. RTS and DTR control signals automatically switch the ESP32 into programming mode.

The problem occurs because the converter asserts DTR before RTS, resetting the ESP32.

Resolution

No fix is planned.

Workaround

For debugging, connect the USB cable before powering the device. This behavior does not affect firmware flashing.

ERRWB-MGEv30002: Incorrect reception of long RS-485 packets and incorrect Modbus TCP operation

Affected devices

All WB-MGE v.3 devices running firmware up to and including 1.0.3

Description

Incorrect reception of RS-485 packets longer than 120 bytes:

  • in Modbus TCP mode, reading device settings in the Serial devices driver settings in the Wiren Board controller web interface fails;
  • in Modbus TCP mode, more than 57 registers cannot be read at once;
  • in transparent gateway mode, device responses are split into 120-byte chunks. Third-party masters may receive incorrect responses, and receiving a complete response may take much longer.

Incorrect Fast Modbus operation in Modbus TCP mode when requesting events:

  • in Modbus TCP mode, the gateway blocks slave responses indicating that no events are available.

Response timeout in Modbus TCP mode:

  • at high RS-485 baud rates, reading many registers may time out while waiting for the slave response.

Cause and details

The firmware contains the following errors:

  • the maximum UART receive-buffer size is not accounted for, so packets longer than 120 bytes are split into several packets. As a result, slave responses are processed incorrectly in Modbus TCP mode;
  • the firmware does not account for 5-byte responses to Fast Modbus broadcast requests. Consequently, the gateway blocks slave no-events responses in Modbus TCP mode;
  • internal FreeRTOS task-switching delays are not accounted for, potentially causing slave-response timeouts in Modbus TCP mode.

Resolution

Fixed in firmware 1.0.4, dated 15 December 2025.

Workaround

Update to firmware 1.0.4

ERRWB-MGEv30003: Unreliable control of I/O Bus, Vout, termination and failsafe bias

Affected devices

All WB-MGE v.3 devices running firmware up to and including 1.0.5

Description

Signals generated by the port-expander chip may occasionally fail to change physically when toggled in the gateway web interface:

  • Vout power output;
  • I/O Bus enable (WB-MIO chip);
  • RS-485 termination resistors;
  • RS-485 failsafe-bias resistors.

Cause and details

The firmware does not account for the port-expander driver's read-modify-write behavior. Concurrent access from different threads can therefore cause output changes to be lost.

Resolution

Fixed in firmware 1.0.6, dated 29 December 2025.

Workaround

Update to firmware 1.0.6

ERRWB-MGEv30004: Firmware update fails over Wi-Fi

Affected devices

All WB-MGE v.3 devices running firmware up to and including 1.0.6

Description

Firmware updates through the web interface often fail over Wi-Fi. The firmware is not updated; the previous firmware remains functional.

The same problem may occasionally occur over Ethernet.

Cause and details

High CPU load, particularly over Wi-Fi, triggers the Task Watchdog Timer while preparing the update by erasing the flash region for the new firmware. The device reboots before receiving the new firmware.

Resolution

Fixed in firmware 1.0.7, dated 26 January 2026.

Workaround

Update to firmware 1.0.7.

If updating fails:

  • use an Ethernet connection for the update;
  • disconnect all attached devices and external TCP connections;
  • alternatively, update the firmware in Factory.

ERRWB-MGEv30005: IP address cannot be saved in Firefox

Affected devices

All WB-MGE v.3 devices running firmware up to and including 1.0.6

Description

Changing the IP address in the web interface does not work.

Cause and details

When changing and saving an IP address in Firefox, the data is not updated: the IP address returns to its previous value after saving.

Resolution

Fixed in firmware 1.0.7, dated 26 January 2026.

Workaround

Update to firmware 1.0.7 or use another browser, such as Google Chrome.