Assumption: You have built the cable, installed CP2102 drivers (via Zadig or official SiLabs), and have the .hex file ready.
Advice wanted from other users of XHDATA D-808 : r/shortwave xhdata d-808 firmware update
The . The device is a dedicated DSP receiver without a data-transfer interface (the USB port is for charging only), and the manufacturer does not release firmware files for public download. Hardware Revisions vs. Firmware Updates Assumption: You have built the cable, installed CP2102