What are the magic_number firmware_id and sd_id fields in SoftDevice Information Structure?

[Elias]

I haven't found specific documentation on this so I would like to be absolutely certain that the fields in the softdevice info structure are used how I think they're used.

magic_number: always the same across all Nordic SoftDevices

sd_id: always the same for a particular SoftDevice (e.g. s132 4.0 to 5.0) but not between SoftDevices (e.g. s132 to s130)

firmware_id: actually not sure what this identifies

[Martin Lesund]

Hi Elias,

• magic_number: always the same across all Nordic SoftDevices. 0x51B1E5DB 
• sd_id:  always the same for a particular SoftDevice. ex. 132 for s132 and 140 for s140
• firmware_id: is unique for every Softdevice and is sent over the air when version exchange is being done. In the package "LL_VERSION_IND"