Select the firmware file in the tool and click "Start" or "Flash".
With your device in flash mode and connected to your computer, use the Coolsand RDA Flash Tool to select the firmware you wish to install and follow the on-screen instructions. coolsand rda flash tool link
Click "Start" in the tool. Once the process is complete, a green bar or "Success" message will appear. Important Precautions Select the firmware file in the tool and
: Verify the correct boot key for your exact hardware model. Redownload the firmware file to ensure it is not corrupted. Write Timeout Error Once the process is complete, a green bar
Restore lost IMEI numbers after a firmware flash.
The technology is obsolete. RDA Microelectronics was acquired, and Coolsand chips are no longer used in modern smartphones (which now use MediaTek, Snapdragon, or Unisoc). Consequently, official developer support has vanished, and the only versions available are those archived by third-party repair technicians.