Implications of changing bootloader size

RE: Implications of changing bootloader size

rabiaasl — Thu, 07 Apr 2016 17:46:51 GMT

Do you need to decrease the size of the application if you increase the size of the bootloader? My application isn't that large, and likely does not use all the allocated memory. As well, how would this change affect duel bank vs. single bank DFU? I'm doing DFU over BLE. I'm also on the latest SDK v11 (not alpha) and the 2.0.0 soft device.

RE: Implications of changing bootloader size

sidekick — Tue, 07 Jul 2015 11:17:36 GMT

Thank you @Hung Bui for suggestions and clarification.

RE: Implications of changing bootloader size

Hung Bui — Fri, 19 Jun 2015 15:06:37 GMT

@sidekick:

If you think your bootloader gonna expand, you can simply move the start address from the current address 0x3c000 down a little bit to give some headroom for future development. But if you don't plan to have BLE or UART DFU, I don't think your bootloader's size would be much bigger than our bootloader (unless you have extra features such as encryption or smth). Make sure you remove the BLE/UART code when you implement yours.

I don't think anything else need to be taken care of except for the change of the start address of the bootloader. You can have a look here, where we change the optimization level of the bootloader and the size got much bigger.

2 . Yes you can use binary file. What transmitted over the air is actually binary image file. So even if you give hex file to the DFU master, it will convert to binary. Most of our DFU master now accept both .hex and .bin file.