3 Replies Latest reply on Feb 20, 2019 9:27 PM by PraveenM_86

    Erased Fixed Mode Vector and Fixed Reset Vector

    ryko_3280246

      Hello,

       

      What happens if erase FMV and FRV Vectors on MB91460 mcu family?

      can they be restored?

        • 1. Re: Erased Fixed Mode Vector and Fixed Reset Vector
          PraveenM_86

          Please check MB91F460 TRM. In chapter 53 (Fixed Mode-Reset Vector) it is mentioned that these two vectors are independent from the flash and cannot be erased. This means that in internal vector mode (MD[2:0]), after reset the BootROM is always  executed at address 0xBFF8.

           

          Additional information:

          By default the user program entry address is set to Flash address 0xF4000. This can be changed by the boot security vectors BSV1 (0x148004) and BSV2 (0x14800C) in order to set a new entry address and to skip the internal bootloader managed by the BootRom (see also figure 53.2-2).

          • 2. Re: Erased Fixed Mode Vector and Fixed Reset Vector
            ryko_3280246

            When I deleted the sector that contains Fixed Mode Vector and Fixed Reset Vector, and I tried write the new data in this sector, the processor stuck off.

            Since then, bootROM never started, I don't get ACK response from bootROM.

            • 3. Re: Erased Fixed Mode Vector and Fixed Reset Vector
              PraveenM_86

              As mentioned, FMV cannot be erased. What does they mean with they don’t get ACK response from the BootROM? The BootROM is providing a simple internal bootloader in case BSV1/BSV2 have no valid data programmed. If BSV1/BSV2 have valid data, the internal bootloader is skipped and no communication can be done via the internal bootloader. In that case a user software must already be programmed which is communicating via an interface (like a CAN bootloader) in order to re-program or to erase the Flash. If this software is not present in the Flash, the Flash can only be erased by a parallel Flash programmer