Lets split eh (#3120)

* Line ending stuff again

* Added Let's Split Eh? Files and updated #USE_IC2 checks to also include th EH revision (can only be used in I2C)

* Added personal keymap, updated some of the EH files

* Created new keyboard file for testing "lets_split_eh" will merge into lets_split once fully functional

* Added split code from lets_split, removed pro micro imports and LED code

THIS IS WORKING CODE, WITHOUT RGB AND BACKLIGHT

* Took back original Lets Slit files for the lets_split keyboard, working in the lets_split_eh folder for now

* Updated eh.c

* More rework of the I2C code, added global flags for split boards.

* Introduced RGB over I2C, having weird edge case issues at the moment though

* Fixed weird I2C edgecase with RGB, although still would like to track down route cause..

* Changed RGB keycodes (static ones) to activate on key-up instead of key-down to elimate weird ghosting issue over I2C

* Lots of changes, mainly externalized the Split keyboard code and added logic for only including when needed.

- Added makefile option "SPLIT_KEYBOARD" that when = yes will include the split keyboard files and custom matrix
- Split keyboard files placed into quantum/split_common/
- Added define option for config files "SPLIT_HAND_PIN" FOr using high/low pin to determine handedness, low = right hand, high = left hand
- Cleaned up split logic for RGB and Backlight so it is only exectuted / included when needed

* Updated documentation for the new makefile options and #defines specific to split keyboards

* Added a bit more info to docs, so people aren't confused

* Modifed Let's Split to use externalized code, also added left and right hand eeprom files to the split_common folder

* Removed some debugging from eh.c

* Small changes to keyboard configs. Also added a default keymap (just a copy of my that_canadian keymap).

* Added a README file to the Let's Split Eh?

* Changed it so RGB static updates are done on key-up ONLY for split boards rather than all boards. Also fixed leftover un-used variable in rgblight.c

* Updated default keymap and my keymap for Let's Split Eh? Updated the comments so it reflects RGB control, and removed audio functions.

* Fixed lets_split_eh not having a default version

* Removed "eh" references from lets_split folder for now

* Took lets_split folder from master to fix travis build errors, weird my local was overriding.

* Changed LAYOUT_ortho_4x12_kc -> LAYOUT_kc_ortho_4x12 to match bakingpy and others

* Removed rules.mk from my lets_split keymap, not needed

* Updated the config_options doc to better explain the usage of "#define SPLIT_HAND_PIN"

2 files changed, 16 insertions, 0 deletions

diff --git a/docs/config_options.md b/docs/config_options.md
index 94233cadcf..d728a49c3e 100644
--- a/docs/config_options.md
+++ b/docs/config_options.md
@@ -179,6 +179,16 @@ If you define these options you will enable the associated feature, which may in
 * `#define MOUSEKEY_MAX_SPEED 7`
 * `#define MOUSEKEY_WHEEL_DELAY 0`
 
+## Split Keyboard Options
+
+Split Keyboard specific options, make sure you have 'SPLIT_KEYBOARD = yes' in your rules.mk
+
+* `#define SPLIT_HAND_PIN B7`
+  * For using high/low pin to determine handedness, low = right hand, high = left hand. Replace 'B7' with the pin you are using. This is optional and you can still use the EEHANDS method or MASTER_LEFT / MASTER_RIGHT defines like the stock Let's Split uses.
+  
+* `#define USE_I2C`
+  * For using I2C instead of Serial (defaults to serial)
+
 # The `rules.mk` File
 
 This is a [make](https://www.gnu.org/software/make/manual/make.html) file that is included by the top-level `Makefile`. It is used to set some information about the MCU that we will be compiling for as well as enabling and disabling certain features.
@@ -232,3 +242,5 @@ Use these to enable or disable building certain features. The more you have enab
   * Unicode
 * `BLUETOOTH_ENABLE`
   * Enable Bluetooth with the Adafruit EZ-Key HID
+* `SPLIT_KEYBOARD`
+  * Enables split keyboard support (dual MCU like the let's split and bakingpy's boards) and includes all necessary files located at quantum/split_common
diff --git a/docs/getting_started_make_guide.md b/docs/getting_started_make_guide.md
index a57edcb984..e515411901 100644
--- a/docs/getting_started_make_guide.md
+++ b/docs/getting_started_make_guide.md
@@ -133,6 +133,10 @@ This consumes about 5390 bytes.
 
 This enables [key lock](feature_key_lock.md). This consumes an additional 260 bytes.
 
+`SPLIT_KEYBOARD`
+
+This enables split keyboard support (dual MCU like the let's split and bakingpy's boards) and includes all necessary files located at quantum/split_common
+
 ## Customizing Makefile Options on a Per-Keymap Basis
 
 If your keymap directory has a file called `rules.mk` any options you set in that file will take precedence over other `rules.mk` options for your particular keyboard.