RustyRover

This is the firmware for a cheap robot car kit, which had its brains replaced by an NRF52832 board. As implied by the name, the firmware is written in Rust. RustyRover is a hobby project aimed at learning about

• Embedded Rust
  • Rust and its ecosystem
  • The specialized tooling
  • RTIC
• A new chip (the nRF52)
• A new communication stack (BLE)

Status

The softdevice and RTIC are set up to nicely play together. BLE advertisement works and the basics of event handling are implemented. Everything is in a proof-of-concept state.

Setup

• Install nightly rust, probe-run:

$ rustup update
$ cargo install probe-run probe-rs-cli

• Flash softdevice s112 v7.3.0 (after downloading from nRF website):

$ probe-rs-cli erase --chip nrf52832
$ probe-rs-cli download --chip nrf52832 --format hex s112_nrf52_7.3.0_softdevice.hex

• Connect to target using debug probe supported by probe-rs.

Running

$ export DEFMT_LOG=debug
$ cargo run

Notes

• As dwt-systick-monotonic depends on fugit 0.3.3, you need at least rust 1.57 to compile
• nrf-softdevice* requires nightly features, which are enabled via rust-toolchain.toml. Make sure to run rustup update inside this folder.
• Good rtic examples: https://github.com/mciantyre/teensy4-rs/blob/master/examples/rtic_blink.rs
• The SoftDevice and defmt don't go well together. Using defmt in the event notification interrupt makes the SoftDevice assert, possibly because it detects some debug-fishiness going on. It definitely doesn't have anything to to with blocking the notification interrupt, as busy-looping for 500ms is no problem. Rerouting the event to another RTIC task works around this issue (see softdev_event_notify_interrupt and softdev_event_notify in src/main.rs)