Advanced firmware upload uptions

• Login to Carambola and download binary image to RAM. (Alter IP and path to match your binary image location)

scp test@192.168.0.104:/home/test/carambola_tester/bin/ramips/openwrt-ramips-rt305x-carambola-squashfs-sysupgrade.bin /tmp

• Perform upgrade procedure.

mtd -r write /tmp/openwrt-ramips-rt305x-carambola-squashfs-sysupgrade.bin firmware

• I assume you have latest firmware with UART support. If no, update firmware.
• Setup UART connection.
• Power on Carambola.
• Wait till boot menu appears and press "4"

Please choose the operation:  
  1: Load system code to SDRAM via TFTP.  
  2: Load system code t hen write to Flash via TFTP. 
  3: Boot system code via Flash (default). 
  4: Entr boot command line interface. 
  7: Load Boot Loader code then write to Flash via Serial.  
  9: Load Boot Loader code then write to Flash via TFTP. 

• To erase the flash type command:

erase 0xbf050000 0xbf7fffff

• To transfer binary image to RAM type command:

loadb

• To copy uploaded firmware from RAM to FLASH type command:

cp.b 0x80100000 0xbf050000 0x600000  

• Reboot Carambola after completing these steps. It should boot new firmware firmware.

New Carambola's are shipped with enabled "serial upgrade" bootloader. If you have purchased it earlier, for some reason you might need to have this feature enabled. There is how to do it.

• Start Terminal and TFTP programs.
• Download firmware image from here (check our github section if this is latest firmware available)
• Connect UART, LAN, and power (or POE) cables.
• Power on your Carambola.
• You should see menu like this:

Please choose the operation:
  1: Load system code to SDRAM via TFTP.  
  2: Load system code then write to Flash via TFTP. 
  3: Boot system code via Flash (default). 
  4: Enter boot command line interface. 
  9: Load Boot Loader code then write to Flash via TFTP. 

• Select <9>
• Enter Carambola and TFTP server addresses
• Enter bootloader file name you wish to upload and press enter. This is it. Now there is no way out. There are big chances for you to brick Carambola at this stage if you cut power or press any keys like CTRL+C.

9: System Load Boot Loader then write to Flash via TFTP. 
 Warning!! Erase Boot Loader in Flash then burn new one. Are you sure?(Y/N)
 Please Input new ones /or Ctrl-C to discard
      Input device IP (10.10.10.123) ==:192.168.101.223
      Input server IP (10.10.10.3) ==:192.168.101.52
      Input Uboot filename () ==:uboot_3_3_5.bin

After a while Carambola should reboot and previous boot menu should look like this:

Please choose the operation:  
  1: Load system code to SDRAM via TFTP.  
  2: Load system code t hen write to Flash via TFTP. 
  3: Boot system code via Flash (default). 
  4: Entr boot command line interface. 
  7: Load Boot Loader code then write to Flash via Serial.  
  9: Load Boot Loader code then write to Flash via TFTP. 

• Congratulations. You have succeeded upgrading bootloader.

This method is recommended for novices. Connect Carambola web interface, browse for firmware upgrade, select file and press upgrade.