Board Recovery

Set Up or Recover Your Board

Use this page to install or recover a board. It installs the Papilio ESP Bootloader and a compatible FPGA-Companion app in one USB operation. Everything happens in this browser tab over USB and your home WiFi. Nothing is installed on your computer, and your WiFi credentials never leave your machine except to the board itself.

Already set up? For everyday use — JTAG SRAM, recovery mode, or OTA firmware updates — use the full Papilio Loader — Web Edition instead.

Serial log 

    


    
    

      

        1
        
Install / Recover ESP32 (USB)

      

      

        We've bundled the recovery image
        (checking…) right here. Plug
        the board in over USB and flash it to restore the new Papilio ESP Bootloader,
        even if the current firmware is rebooting or is an older FPGA-Companion image.
      

      

        If needed, hold down the ESP32-S3's BOOT button while powering
        on the board over USB to enter factory boot mode. When connected, the Retrocade's
        ESP32 usually appears as two serial ports; choose the lower-numbered one in the
        browser's serial-port chooser. If you are unsure which ports belong to the board, unplug
        it and note which ports disappear, then plug it back in and watch for those ports
        to return.
      

      

        Contains the latest
        Papilio ESP Bootloader
        (source) +
        FPGA-Companion
        (source).
      


      

        
        
      


      

        Use a different firmware file instead
        

          
        

      


      
      

    


    
    

      

        2
        
Connect to Your WiFi

      

      

        Written directly into the board's flash over USB — never sent over the internet. The board
        then restarts into FPGA-Companion, joins your WiFi (2.4 GHz only), and reports its IP here.
        Already flashed and connected to WiFi from a previous session? Plug it into
        USB, click Find My IP below, then press RESET — no need to resend credentials.
      


      

        
        
        
        
      

      


      

        Device IP:
        waiting for board…
        
        
      

    


    
    

      

        3
        
Install the Latest A2600 Core

      

      

        Downloads the latest published Atari 2600 FPGA core and writes it to the board's FPGA
        flash. The page first switches the board into the Papilio ESP Bootloader (which does
        the flashing), then returns it to FPGA-Companion. Sent directly from this browser tab — over WiFi if the device's IP is known
        (fastest), or over the USB connection from Step 1/2 if it isn't. No cloud relay either way.
      


      

        
      


      
      


      

        Flash a different bitstream instead
        

          Only Gowin's headerless .bin ("Binary File") bitstream export is
          supported — .fs exports aren't parsed by the firmware yet.
          Recovery requires a known IP (WiFi OTA only for now).
        

        

          
          
          
        

        

          
          
        

        

      

    


    
    

      

        4
        
Load a Demo Game ROM

      

      

        Sends the Papilio Splash demo ROM to the A2600 core installed in Step 3. Insert a
        FAT-formatted SD card first — the ROM is saved to the card and then
        started on the core. Requires WiFi (a known device IP from Step 2).