Firmware Upgrading - Quectel BG770A-GL TE-A User Manual

4.4. Firmware Upgrading

If the module can be turned on normally, you can directly upgrade the firmware through the debug UART
on the TE-A. If the module cannot be turned on normally, you can refer to the following steps to enter the
recovery mode and upgrade the firmware forcibly. For more information about the recovery mode, please
refer to document [2].
1. Disconnect the Micro-USB cable of UART_DBG.
2. Short-circuit the two test points (DBG_TXD and DBG_RXD), and press S303 (RESET button) at least
100 ms on the UMTS&LTE EVB to reset the BG770A-GL.
3. Disconnect DBG_TXD and DBG_RXD.
4. Insert the Micro-USB cable of UART_DBG and upgrade the firmware through this UART.
BG770A-GL_TE-A_User_Guide
Figure 8: Main UART Communication
LPWA Module Series
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