This post is older than 2 years and might not be relevant anymore
More Info: Consider searching for newer posts

S110 7.0.0 : Can I write my own MBR?

Hi

I am looking at section 9.1 of the S110 Softdevice Specification v1.3A and the release notes for 7.0.0-2.alpha where I see that an application now starts at 0x15000 which is to make room for an extra 4Kbytes in the softdevice 7.0.0

Can I assume that this extra 4kbytes is used for the new Master Boot Records? The spec further states ..

[b]The MBR is first placed in flash memory where the System Vector table resides. All exceptions (reset, hard fault, interrupts SVC), are processed first by the MBR. The MBR is not updated between versions of the SoftDevice, meaning during an update process, the MBR is never erased. The MBR ensures safe restart of the copy process if an unexpected reset occurs. [/b]

You also further state that the softdevice is no longer protected via the UICR.

Does this mean you could provide a template MBR project so that I could create by own bootloader (and remove the need for the other one at the high end of the flash) and thereby ensure that I could always upgrade a softdevice + application image regardless of any API changes you may make in the future. For example, you have confirmed in seperate exchanges that over the air upgrades is not guaranteed to work for S110 v7 to S100 v8 (when and if it happens).

If this ability is expedited by Nordic, then we may be able to ensure uart and OTA upgrades regardless of any future api changes to softdevice in the future.

Thank you in advance

Related