Update 'Software Setup'

Software-Setup.md

@@ -1,4 +1,62 @@
 # Software Setup
-## Installing Rust Components
+## Prerequisites
++ Native Rust compiler managed by [rustup](https://rustup.rs/)
++ Basic native C development tools
++ A working `git` installation
+## Installing Rust Cross-compiling Components
+    > rustup target add thumbv7m-none-eabi
+
 ## Flash/Debug Tools
+### Debian/Ubuntu Prerequisites
+To build the Rust debugger tools, the following packages need to be installed:
+
+    > sudo apt install -y pkg-config libusb-1.0-0-dev libftdi1-dev
+
+You may also need to remove old versions of libusb:
+
+    > sudo apt remove libusb-dev
+### Windows Prerequisites
+If you don't have `vcpkg`, install that first:
+
+    > git clone https://github.com/microsoft/vcpkg
+    > .\vcpkg\bootstrap-vcpkg.bat
+    
+Then use it to install `libusb` and `libftdi`
+
+    > vcpkg install libusb:x64-windows-static-md libftdi1:x64-windows-static-md
+    
+### macOS Prerequisites
+If you don't have `brew` installed, install that first:
+
+    > /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+
+Then install `libftdi`
+
+    > brew install libftdi
+    
+### Install cargo plugins
+These are the tools that interface `cargo` to the STLinkV2 clone:
+
+    > cargo install cargo-flash
+    > cargo install cargo-embed
+
+### Windows STLink Drivers
+You won't be able to use the STLinkV2 clone debugger without the [STLink driver](https://www.st.com/en/development-tools/stsw-link009.html).
+
+### Linux `udev` rules
+This `udev` rule lets you use the STLinkV2 clone without root privilege.
+
+Create the file `/etc/udev/rules.d/70-st-link.rules` with the contents shown below.
+
+```
+# ST-LINK/V2
+ATTRS{idVendor}=="0483", ATTRS{idProduct}=="3748", TAG+="uaccess"
+
+# ST-LINK/V2-1
+ATTRS{idVendor}=="0483", ATTRS{idProduct}=="374b", TAG+="uaccess"
+```
+Then reload all the udev rules with:
+
+    sudo udevadm control --reload-rules
+
 ## Crate Setup