Update readme

keyboards/bananasplit/README.md

@@ -1,3 +1,29 @@
-# BananaSplit60
+# BananaSplit60 keyboard firmware
 
 Ported from evangs/tmk_keyboard
+
+## Quantum MK Firmware
+
+For the full Quantum feature list, see [the parent readme](/).
+
+## Building
+
+Download or clone the whole firmware and navigate to the keyboards/bananasplit folder. Once your dev env is setup, you'll be able to type `make` to generate your .hex - you can then use the Teensy Loader to program your .hex file.
+
+Depending on which keymap you would like to use, you will have to compile slightly differently.
+
+### Default
+
+To build with the default keymap, simply run `make default`.
+
+### Other Keymaps
+
+Several version of keymap are available in advance but you are recommended to define your favorite layout yourself. To define your own keymap create a folder with the name of your keymap in the keymaps folder, and see keymap documentation (you can find in top readme.md) and existant keymap files.
+
+To build the firmware binary hex file with a keymap just do `make` with a keymap like this:
+
+```
+$ make [default|jack|<name>]
+```
+
+Keymaps follow the format **__\<name\>.c__** and are stored in the `keymaps` folder.