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TM4C129XNCZAD: Can TM4C129XNCZAD boot from external Flashrom?

Part Number: TM4C129XNCZAD

Dear Sir

About Tiva Tm TM4C129XNCZAD Microcontroller, I have two questions in below.

Q1) Although there is internal boot FlashRom inside MCU.

But we still would like to have boot from external FlashROM function.

Does this MCU has boot from external flash-rom capability?

If yes, do you have application note related document?

Q2) Where can I find TM4C129XNCZAD (ZAD package) reference circuit & PCB brd file,

and Evaluation kit?

  • Hello David,

    I am not entirely familiar with how external Flash ROM works for booting, but based on your graphic here it uses SPI to connect to the MCU? If so you can make a Flash boot loader with the proper protocol for the your Flash ROM to handle this.

    Our TivaWare Bootloader User's Guide is the best resource for this: https://www.ti.com/lit/pdf/spmu301

    For the evaluation kit, please see our Development Kit https://www.ti.com/tool/DK-TM4C129X

    Best Regards,

    Ralph Jacobi

  • Thanks,

    From your information, it looks like boot loader code is customized design by user.

    But I wonder how the bootloader fetch/load external ROM's program code into SRAM for CPU operation.  

    Do you have any external boot function's reference bootloader code and circuit?

    And some few question in below...

    1. Support FlashROM type & Max. capacity size

            => Can we use SPI NOR flash ROM? (Ex. Winbond W25Q16 series)

    1. What MCU Interface pins can handle the external Boot-up ROM?

    Best Regards

    David

  • Hello David,

    Do you have any external boot function's reference bootloader code and circuit?

    We do not, that is not an application that has come up before in my years of TM4C support so it is not something we have considered putting together collateral for.

    1. Support FlashROM type & Max. capacity size

            => Can we use SPI NOR flash ROM? (Ex. Winbond W25Q16 series)

    In principle you can use SPI NOR Flash via QSSI, but you'd have to add that sort of functionality to the Flash bootloader and verify operation. Probably not trivial, but definitely doable.

    What MCU Interface pins can handle the external Boot-up ROM?

    When using the Flash bootloader you would not be pin restricted. One of the top reasons Flash bootloader is used is when the ROM bootloader pins do not align with what is desired to use.

    Best Regards,

    Ralph Jacobi