Board memory layouts

This page documents the RRAM (flash) and SRAM partition layouts for supported bm_* board configurations. Use the three-level tabs (DK → SoC → SoftDevice) to view layouts for each combination. Each diagram shows the partitions from low address (bottom) to high address (top), with hex addresses on the left and sizes on the right.

The diagrams are auto-generated from the board devicetree sources during the documentation build, so they always match the current devicetree files.

Partition descriptions

The diagrams use descriptive names. The table below maps each to the devicetree partition label and describes its role.

RRAM partitions

Partition (diagram)	DTS label	Description
MCUboot	boot	MCUboot bootloader image. Present only in MCUboot configurations.
Storage: Peer Manager	peer_manager	Persistent storage for Bluetooth bonding and peer data.
Storage: User data	storage0	General-purpose non-volatile storage using BM ZMS.
Application	slot0	Main application firmware image.
Firmware Loader	slot1	Firmware loader / secondary slot for DFU. Present only in MCUboot configurations.
SoftDevice	softdevice	Nordic SoftDevice Bluetooth LE stack binary.
Metadata	metadata	MCUboot metadata region. Present only in MCUboot configurations.

SRAM partitions

Partition (diagram)	DTS label	Description
KMU reserved	—	128 bytes reserved by the Key Management Unit at the start of SRAM (synthetic region, no partition label in DTS).
SoftDevice RAM	softdevice_ram	Allocated RAM for the SoftDevice. Consists of SoftDevice static RAM with a size depending on the SoftDevice variant (S115 vs S145) and SoftDevice Dynamic RAM with a size depending on the number of connections and required buffer sizes.
Application RAM	app_ram	RAM available for the application.
Retained RAM	RetainedMem	Retained memory region for MCUboot settings persistence across resets. Present only in MCUboot configurations.

Memory layout diagrams

Select DK → SoC → SoftDevice to view RRAM and SRAM layout diagrams.

Note

The total SRAM size shown in these diagrams may differ from the total given in the Datasheet. Reserved regions, “VPR saved context” and “Protected RAM”, are part of the SRAM memory map but are not shown as partitions in the diagrams. For the complete layout, see the Memory map section in the device-specific Datasheet.

nRF54L15-DKnRF54LM20-DKnRF54LS05-DKnRF54LV10-DK

nRF54L15nRF54L10nRF54L05

Total RRAM: 1524 KB | Total SRAM: 256 KB

S115S145

S115

S115 + MCUboot