ESP firmware for DreamcastHDMI/DCHDMI consists of 2 files
    
        - <flash_size>-firmware.bin
 The firmware itself.
- <flash_size>-spiffs.bin
 Flash filesystem.
Additionally there is the index.html.gz for this version for WiFi-update
    
        - esp.index.html.gz
 index.html file for self-update.