Vendor-Specific Layer

This layer consists of memory-mapped register, interrupt, and peripheral mappings, and also possibly of DSO (Drone Serial Output) implementations. In this section we will overview drone-nrf-map and drone-nrf91-dso crates as examples of the vendor-specific layer.


drone-nrf-map collection of crates is purely declarative. We try to automatically generate as much code as possible from vendor-provided CMSIS-SVD files. Generation of memory-mapped register bindings is highly parallelizable. Therefore it's splitted into 12 crates, which are named from drone-nrf-map-pieces-1 to drone-nrf-map-pieces-12 and compiled by cargo in parallel. drone-nrf-map-pieces-* crates are all re-exported by single drone-nrf-map-pieces crate, which can be further used by peripheral bindings.

Not all bindings can be auto-generated. We also manually declare peripheral mappings. For the sake of compile-time parallelization, each peripheral type is declared in its own crate (e.g. drone-nrf-map-periph-uarte.) Periheral crates are opt-in, they are enabled by activating corresponding cargo features for drone-nrf-map crate.

Finally, drone-nrf-map-pieces and drone-nrf-map-periph-* crates are all re-exported by drone-nrf-map crate.

Drone Serial Output

If the target doesn't implement usual hardware logging, as in case with nRF9160, we provide a software logging implementation. It uses special Drone Serial Output protocol to provide features similar to hardware SWO. Namely splitting the output into different ports and forming atomic packets.

drone-nrf91-dso implementation is based on software output FIFO, and utilizes one of generic built-in UART peripheral.