custom memory layout

[B.Ho]

Hi, there~

I'm trying to make my own bootloader and starting with the secure bootloader sample code.

The problem is the orignal bootloader, that is compiled with secure bottloader sample code, almost reach the maximun size.

As I know, the size of bootloader in flash memory layout is 24k, and the orignal bootloader is more than 23k.

So I want to make more space for the bootloader.

The question is:

1. How to customize the memory layout in order to get more space for bootloader?

2. Is there any document about memory layout for softdevice s340?

my development environment is:

OS: windows 10

IDE: SES

SDK: nRF5_SDK_15.3.0_59ac345

SD: s140_6.1.1

Board: nRF52840 DK

Thanks~~

[Simonr]

Hi

1. You need to adjust IROM settings for the project. If you need more space for the bootloader you can allocate more by reducing the start address (IROM start, and increase the size setting with the same amount). You can see an example on how this is done in the debug variant of the bootloader project. Note that it is not possible to increase the bootloader size after initial programming without doing a full chip erase, since the bootloader start address is stored in the UICR register.

2. You can find this documentation over at thisisant's web pages, but you have to register as a user, as they are responsible of the s340 SoftDevice. But the RAM start and Flash start values, as well as how to change these can be found here in our memory adjustment tutorial.

Minimum RAM Start address: 0x20002000

Flast Start address: 0x31000

Best regards,

Simon

[Andy]

Off-topic: What? The softdevice is not developed by Nordic?

[Simonr]

Sorry, yes it is, but thisisant has modified it implemented ANT functionalities into the s340. I have rephrased my previous reply to avoid confusion.