Bootloader ROM / RAM configurations for chip XXAA

[Sébastien Despont]

After checking bootloader example from the SDK version 10, I am not able to find appropriate ROM / RAM addresses configurations for 16kb RAM chip. The Bootloader examples use chip version XXAC (32kb RAM) and I would like to know addresses for chip XXAA (16kb RAM).

Here is the configuration for XXAC chip :

There is a lot of information regarding the bootloader like this good FAQ or implementation details but nothing about the ROM / RAM addresses. I really doubt about it, but maybe they are always identicals for all chips versions ?

[bjorn-spockeli]

The bootloader ROM/RAM settings will vary depending on which chip variant( 256kB Flash and 32kB RAM/16kB RAM or 128kB Flash and 16kB RAM) and which SoftDevice you're using.

In your specific case,where your're using a nRF51422 xxAA variant with 256kB Flash, 16kB RAM and the S130 v1.0.0 SoftDevice, the correct settings are then:

IROM1: Start: 0x3C000 Size:0x3C00

IRAM1: Start: 0x20002C00 Size: 0x1380

IRAM2: Start: 0x20003F80 Size: 0x80

You can find the ROM/RAM requirements for the SoftDevices in their respective SoftDevice Specifications or release notes.

Update:

The S110 v8.0.0 does not require as much RAM as the S130 v1.0.0, so the settings should be:

IROM1: Start: 0x3C000 Size:0x3C00

IRAM1: Start: 0x20002000 Size: 0x1F80

IRAM2: Start: 0x20003F80 Size: 0x80

-Bjørn

[Sébastien Despont]

Thank you for your answer! In my case, the chip is nRF51822 XXAA used with S110 v8.0.0 softdevice, is it the same values than you posted?

[bjorn-spockeli]

The S110 v8.0.0 does not require as much RAM as the S130 v1.0.0, see my updated answer.

[Sébastien Despont]

Thanks again. I have just looked in the release note of the SoftDevice and I have not found the values mentioned in your answer. Where can I find this information?

[bjorn-spockeli]

You'll have to look in the S110 v8.0.0, found here, specifically section 11.2 Memory resource map and usage.