For firmware, search for your exact PCB version (e.g., M88CS2000-GX6605S-V2.0 ).
This is the trickiest part:
Open your receiver's casing and locate the serial communication pins on the motherboard. They are typically grouped together as a 3-pin or 4-pin header and clearly labeled on the circuit board as: (Transmit) RX (Receive) GND (Ground)
Verify you are using the correct boot file for the GX6605S. Using a boot file for a different chipset will prevent the flash process from initiating.
