Ensure you are using a Null Modem Cable (crossed TX/RX) rather than a straight-through serial cable.
Manually installs official or custom firmware when USB or Over-the-Air (OTA) updates are unavailable or failing. ali-rs232-upgrade-tool-v1-2-0 downloader Full
Never turn off the receiver or disconnect the cable during the "burning" phase, as this can permanently damage (brick) the hardware. Overview — ali-rs232-upgrade-tool-v1-2-0 downloader 2