Reflashing OFW over Serial

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If you need to update OFW but you don't have access to a mass storage device like SD or USB or the network, you can get the new OFW image over a serial connection. It takes a minute or two to download an ofw.rom file at 115200 baud.

You will need binary-download support in your terminal emulator program. TeraTermPRO has it built-in; with minicom you need to install a "bin-xfr" helper program.

First, ensure that you are using 115200 baud; if not:

 ok d# 115200 baud

Of course, you will need to adjust the baud rate on your terminal emulator program if you switched rates.

Start OFW's binary downloader:

 ok dlbin

You now have about 16 seconds to begin the download. Tell your terminal emulator to send the ofw.rom image in binary mode. (In TeraTermPRO, check the Binary box in the Send File dialog; in minicom, use bin-xfr as the helper program.) If you forget to use binary mode and then reflash with the resulting downloaded data, you can brick the machine and then you will have to reflash with JTAG or some other recovery method.

When the download finishes, dlbin will wait 5 seconds to see if more data is coming, and then return to the ok prompt.

Tell OFW that new FLASH data has been loaded, then start the reflash:

 ok true to file-loaded?
 ok reflash

If you are using a different base baud rate than 115200, remember to restore that rate on your terminal emulator before restarting OFW. Bold text