Add content from Ferrous Systems.

README.md

@@ -104,18 +104,18 @@ In 2018 the Rust community created an embedded working group to help drive adopt
 - [Writing an OS in rust](https://os.phil-opp.com/) A blog series creating a small operating system in Rust
 -   [MicroRust](https://droogmic.github.io/microrust/) Introductory book for embedded development in Rust on the micro:bit.
 -   [Physical Computing With Rust](https://rahul-thakoor.github.io/physical-computing-rust/) A (WIP) guide to physical computing with Rust on the Raspberry Pi.
--   [Internet of Streams](https://www.youtube.com/playlist?list=PLX44HkctSkTewrL9frlUz0yeKLKecebT1) A video series  by [@jamesmunns] building a bare metal IoT Sensor Node Platform from (nearly) scratch in Rust
 -   [Writing an embedded OS in Rust on the Raspberry Pi](https://github.com/rust-embedded/rust-raspi3-OS-tutorials) A set of tutorials that give a guided, step-by-step tour of how to write a monolithic Operating System kernel for an embedded system from scratch. Runs on the Raspberry Pi 3 and the Raspberry Pi 4.
 -   [Writing embedded drivers in Rust isn't that hard](https://hboeving.dev/blog/rust-2c-driver-p1/) A guide to building an embedded-hal driver. [Part 2](https://hboeving.dev/blog/rust-i2c-driver-p2/)
+-   [Ferrous Systems' Embedded Training Courses: 2020-current edition](https://github.com/ferrous-systems/embedded-trainings-2020) A hands-on training course for beginner and advanced learners of Embedded Rust, based on Nordic Semiconductor's nRF52840 harware. This training was given at Oxidize Conferences and by [Ferrous Systems] to corporate customers.
+-   [Ferrous Systems' Knurling Sessions](https://knurling.ferrous-systems.com/sessions/) are hands-on embedded projects that explore specific concepts using generally available hardware, building full systems and components using microcontrollers, sensors, and actuators.
 
-[@jamesmunns]: https://github.com/jamesmunns
+[Ferrous Systems]: https://ferrous-systems.com
 
 ## Tools
 
 -   [xargo](https://github.com/japaric/xargo) Rust package manager with support for non-default std libraries — build rust runtime for your own embedded system.
     - xargo is great but it's in maintenance mode, [cargo-xbuild](https://github.com/rust-osdev/cargo-xbuild) is catching up as intended replacement.
 -   [svd2rust](https://github.com/japaric/svd2rust) Generate Rust structs with register mappings from SVD files.
--   [μtest](https://github.com/japaric/utest) unit testing for microcontrollers and other no-std systems.
 -   [embedded-hal-mock] Mock implementation of `embedded-hal` traits for testing without accessing real hardware. - ![crates.io](https://img.shields.io/crates/v/embedded-hal-mock.svg)
 -   [bindgen](https://crates.io/crates/bindgen) Automatically generates Rust FFI bindings to C and C++ libraries. - ![crates.io](https://img.shields.io/crates/v/bindgen.svg)
 -   [cortex-m semihosting](https://github.com/japaric/cortex-m-semihosting) Semihosting for ARM Cortex-M processors
@@ -125,6 +125,12 @@ In 2018 the Rust community created an embedded working group to help drive adopt
 -   [cargo-embed](https://probe.rs/guide/1_tools/cargo-embed/) A superset of cargo-flash with additional useful features like configuration file support, a RTT terminal or a GDB server. - ![crates.io](https://img.shields.io/crates/v/cargo-embed.svg)
 -   [cargo-hf2](https://github.com/jacobrosenthal/hf2-rs)  A small cargo subcommand to download cargo builds to Microsoft UF2 bootloaders via HID USB . - ![crates.io](https://img.shields.io/crates/v/cargo-hf2.svg)
 -   [uf2](https://github.com/sajattack/uf2conv-rs) Converts binary files to Microsoft's UF2 format for copying over to mass storage device uf2 bootloaders - ![crates.io](https://img.shields.io/crates/v/uf2.svg)
+-   [Knurling Tools](https://knurling.ferrous-systems.com/tools/) are developed by [Ferrous Systems] to ease the development process for building, debugging, and testing embedded Rust systems. These tools include:
+    - [Probe Run](https://github.com/knurling-rs/probe-run): a cargo runner to flash and run embedded applications just like you would native applications, including backtraces and panicking behavior
+    - [defmt](https://github.com/knurling-rs/defmt): a highly efficient logging framework that targets resource-constrained devices, like microcontrollers.
+    - [flip-link](https://github.com/knurling-rs/flip-link), a linker wrapper that provides stack overflow protection without an MMU by flipping the standard memory layout of ARM Cortex-M programs
+    - [app-template](https://github.com/knurling-rs/app-template), a `cargo-generate` powered project template for quickly setting up new projects using the Knurling Tools.
+    - [defmt-test](https://github.com/knurling-rs/defmt-test), an embedded test harness that lets you write and run unit tests as if you were using the built-in `#[test]` attribute, but will run on an embedded target
 
 [embedded-hal-mock]: https://crates.io/crates/embedded-hal-mock
 
@@ -973,6 +979,10 @@ These materials may be outdated and reflect earlier practices, but might still b
 -   [Robigalia](https://robigalia.org) general purpose robust operating system in Rust running on secure seL4 microkernel.
 -   [intermezzOS](http://intermezzos.github.io) A small teaching operating system in Rust. A book with some explanations is also included.
 -   [Fearless concurrency](http://blog.japaric.io/fearless-concurrency/) by @japaric — How to easily develop Rust programs for pretty much any ARM Cortex-M microcontroller with memory-safe concurrency.
+-   [Internet of Streams](https://www.youtube.com/playlist?list=PLX44HkctSkTewrL9frlUz0yeKLKecebT1) A video series  by [@jamesmunns] building a bare metal IoT Sensor Node Platform from (nearly) scratch in Rust
+-   [Ferrous Systems' Embedded Training Courses: 2019 edition](https://github.com/ferrous-systems/embedded-trainings/) A hands-on training course for beginner and advanced learners of Embedded Rust, based on Nordic Semiconductor's nRF52 and Decawave's DWM1001-DEV harware. This training was given at Oxidize Conferences and by Ferrous Systems to corporate customers. 
+
+[@jamesmunns]: https://github.com/jamesmunns
 
 ## License