I'm having a hard time sorting through the various documentation files (ROM User's Guide, Bootloader User's Guide, TivaWare sources (C:\TI\TivaWare_C_Series-22.214.171.12477).
What I'm trying to understand are the requirements for a board design in order to support USB firmware upgrades using the ROM bootloader and the on-chip full-speed phy.
Some questions would be:
- how does the ROM bootloader configure the USB phy (on-board or ULPI) when the part erased?
- are there any specific requirements for the clock input in this use case?
- how can I be sure that the USB bootloader *will not* configure the USB port as a host?
(somewhere I saw examples of booting from a USB thumb drive, and I would need to make sure it doesn't try *this* on the board we are designing).
Also, I think I'm having the same problem that some of the other posts mention - the documentation includes a lot of options and even in the source for the bootloader it says the config file is *outside* of the boot_loader folder. So knowing how the bootloader was configured when built for ROM isn't clear.
Is there a project available for download that can rebuild the ROM image (for the purpose of *studying* how it is configured?)