added install steps for using the toolchain

.gitignore

@@ -1 +1,2 @@
 target
+*.code-workspace

README.md

@@ -26,6 +26,37 @@ Planned:
 
 ## Development
 
+To use `cargo run` below you need to have [rustup](https://rustup.rs/) installed. 
+
+    $ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
+To build for the nRF52832 install the correct ARM target.
+
+    $ rustup target add thumbv7em-none-eabihf
+
+`cargo run` uses `arm-none-eabi-gdb`. Use the [latest version from ARM's website](https://developer.arm.com/tools-and-software/open-source-software/developer-tools/gnu-toolchain/gnu-rm/downloads). From Ubuntu 18 onwards, the version obtained from `apt-get` is too old and does not work. Make sure to remove the old toolchain version.
+
+    $ sudo apt remove binutils-arm-none-eabi gcc-arm-none-eabi libnewlib-arm-none-eabi
+
+Untar the new package in your home directory (or wherever you like to have it installed):
+
+    $ tar -xjvf gcc-arm-none-eabi-x-xxxx-qx-update-linux.tar.bz2
+
+Add the new toolchain to your path:
+
+    $ nano ~/.profile
+
+At the bottom of the file add the following line (don't forget to replace xxxx with your version values)
+```
+export PATH=$PATH:/home/(your user)/gcc-arm-none-eabi-x-xxxx-qx-update/bin/
+```
+
+Reboot computer or run in terminal
+
+    $ export PATH=$PATH:/home/(your user)/gcc-arm-none-eabi-x-xxxx-qx-update/bin/
+
+Now you are done installing the ARM toolchain and you can use `cargo run`.
+
+
 ### Flashing (cargo-embed)
 
 Install cargo-embed:
@@ -54,4 +85,16 @@ Run JLinkGDBServer:
 
 Run the code
 
+    $ cd pinetime-rtfm
     $ cargo run [--release]
+
+gdb might notify you that auto-loading has been declined by some safety settings. To add an exception open your `.gdbinit` file
+
+    $ nano ~/.gdbinit
+
+At the bottom of that file add the rule (replace with the location of your own pinetime-rtfm directory location)
+Hint: gdb will suggest what line to add to your `~/.gdbinit` file exactly in its warning message.
+
+```
+add-auto-load-safe-path /home/(user)/git_repos/pinetime-rtfm/pinetime-rtfm/.gdbinit
+```