How to reduce the RAM requirement of the SoftDevice

[tovax]

Hi, All!

I am using nRF51822QFAA with 16KB ram, and S130(sdk 11) for the dual bank bootloader, reference to the s130 releasenote, I config the ram memory start at 0x200013d0, length 0x2c30 for my application.

Because I use the softdevice only for dual bank bootloader, not used in my application, I want to know is it possible to reduce the ram requirement of the softdevice, so I can use more ram for my application.

Best Regards! tovax

[endnode]

Hi, there are two points:

1. S13x V2 Soft Device has several configuration options of LL/L2CAP/ATT/GATT/GAP layers which result in certain RAM requirements. By playing with them you can reduce it but there is certain limit indeed (and I'm afraid you are pretty close to that with 0x13D0).
2. If you don't need BLE functionality in certain use cases then you can disable SoftDevice (= typically reset the chip and boot without SD enabling) and that will require only 4B of RAM (to redirect interrupt vector table from MBR to your app, skipping SD). And once you need it for OTA DFU you can enable it (but then you need to take care about RAM limits).

Cheers Jan

[tovax]

Hi, Cheers Jan, Thank you very much for your reply!