RE: Enterance/Exit times from DFU mode

Edvin — Wed, 01 Jul 2020 14:12:50 GMT

Hello Roi,

This really depends on the applications.

[quote user=""]The time between a successful response for the indication of the DFU characteristic (opcode 1), to it's readvertisement as DFUTarg on the incremented address[/quote]

If your application does a graceful shutdown, this may take as long as the application waits before it reboots.

A Graceful shutdown may include:

Finishing flash write operations if ongoing, disconnecting all connected devices - which would depend on the connection interval. Alternatively if your application has any other tasks it wants to perform before the shutdown. Please check how the buttonless dfu service handles the events.

[quote user=""]The time between DFU end or timeout, and it's readvertising with the app code (the original address)[/quote]

I don't have an exact number, but this would be very dependent on the size of the application. First, when the total application is finished, the bootloader will run through the entire image, and verify the CRC, and that it matches with the CRC from the init packet.

Then, depending on whether it is a single or dual bank, it needs to move the application to the correct place.

I think the easiest way to get a good number is to measure this for your application.

I didn't quite understand the need to know this very accurate. Is there a problem to start scanning for the device before it has started advertising?

BR,

Edvin