Merge remote-tracking branch 'upstream/master'

29 files changed, 1578 insertions, 234 deletions

diff --git a/keyboards/lets_split/common/glcdfont.c b/keyboards/lets_split/common/glcdfont.c
new file mode 100644
index 0000000000..6f88bd23a7
--- /dev/null
+++ b/keyboards/lets_split/common/glcdfont.c
@@ -0,0 +1,276 @@
+// This is the 'classic' fixed-space bitmap font for Adafruit_GFX since 1.0.
+// See gfxfont.h for newer custom bitmap font info.
+
+#ifndef FONT5X7_H
+#define FONT5X7_H
+
+#ifdef __AVR__
+ #include <avr/io.h>
+ #include <avr/pgmspace.h>
+#elif defined(ESP8266)
+ #include <pgmspace.h>
+#else
+ #define PROGMEM
+#endif
+
+// Standard ASCII 5x7 font
+
+static const unsigned char font[] PROGMEM = {
+	0x00, 0x00, 0x00, 0x00, 0x00,
+	0x3E, 0x5B, 0x4F, 0x5B, 0x3E,
+	0x3E, 0x6B, 0x4F, 0x6B, 0x3E,
+	0x1C, 0x3E, 0x7C, 0x3E, 0x1C,
+	0x18, 0x3C, 0x7E, 0x3C, 0x18,
+	0x1C, 0x57, 0x7D, 0x57, 0x1C,
+	0x1C, 0x5E, 0x7F, 0x5E, 0x1C,
+	0x00, 0x18, 0x3C, 0x18, 0x00,
+	0xFF, 0xE7, 0xC3, 0xE7, 0xFF,
+	0x00, 0x18, 0x24, 0x18, 0x00,
+	0xFF, 0xE7, 0xDB, 0xE7, 0xFF,
+	0x30, 0x48, 0x3A, 0x06, 0x0E,
+	0x26, 0x29, 0x79, 0x29, 0x26,
+	0x40, 0x7F, 0x05, 0x05, 0x07,
+	0x40, 0x7F, 0x05, 0x25, 0x3F,
+	0x5A, 0x3C, 0xE7, 0x3C, 0x5A,
+	0x7F, 0x3E, 0x1C, 0x1C, 0x08,
+	0x08, 0x1C, 0x1C, 0x3E, 0x7F,
+	0x14, 0x22, 0x7F, 0x22, 0x14,
+	0x5F, 0x5F, 0x00, 0x5F, 0x5F,
+	0x06, 0x09, 0x7F, 0x01, 0x7F,
+	0x00, 0x66, 0x89, 0x95, 0x6A,
+	0x60, 0x60, 0x60, 0x60, 0x60,
+	0x94, 0xA2, 0xFF, 0xA2, 0x94,
+	0x08, 0x04, 0x7E, 0x04, 0x08,
+	0x10, 0x20, 0x7E, 0x20, 0x10,
+	0x08, 0x08, 0x2A, 0x1C, 0x08,
+	0x08, 0x1C, 0x2A, 0x08, 0x08,
+	0x1E, 0x10, 0x10, 0x10, 0x10,
+	0x0C, 0x1E, 0x0C, 0x1E, 0x0C,
+	0x30, 0x38, 0x3E, 0x38, 0x30,
+	0x06, 0x0E, 0x3E, 0x0E, 0x06,
+	0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00, 0x5F, 0x00, 0x00,
+	0x00, 0x07, 0x00, 0x07, 0x00,
+	0x14, 0x7F, 0x14, 0x7F, 0x14,
+	0x24, 0x2A, 0x7F, 0x2A, 0x12,
+	0x23, 0x13, 0x08, 0x64, 0x62,
+	0x36, 0x49, 0x56, 0x20, 0x50,
+	0x00, 0x08, 0x07, 0x03, 0x00,
+	0x00, 0x1C, 0x22, 0x41, 0x00,
+	0x00, 0x41, 0x22, 0x1C, 0x00,
+	0x2A, 0x1C, 0x7F, 0x1C, 0x2A,
+	0x08, 0x08, 0x3E, 0x08, 0x08,
+	0x00, 0x80, 0x70, 0x30, 0x00,
+	0x08, 0x08, 0x08, 0x08, 0x08,
+	0x00, 0x00, 0x60, 0x60, 0x00,
+	0x20, 0x10, 0x08, 0x04, 0x02,
+	0x3E, 0x51, 0x49, 0x45, 0x3E,
+	0x00, 0x42, 0x7F, 0x40, 0x00,
+	0x72, 0x49, 0x49, 0x49, 0x46,
+	0x21, 0x41, 0x49, 0x4D, 0x33,
+	0x18, 0x14, 0x12, 0x7F, 0x10,
+	0x27, 0x45, 0x45, 0x45, 0x39,
+	0x3C, 0x4A, 0x49, 0x49, 0x31,
+	0x41, 0x21, 0x11, 0x09, 0x07,
+	0x36, 0x49, 0x49, 0x49, 0x36,
+	0x46, 0x49, 0x49, 0x29, 0x1E,
+	0x00, 0x00, 0x14, 0x00, 0x00,
+	0x00, 0x40, 0x34, 0x00, 0x00,
+	0x00, 0x08, 0x14, 0x22, 0x41,
+	0x14, 0x14, 0x14, 0x14, 0x14,
+	0x00, 0x41, 0x22, 0x14, 0x08,
+	0x02, 0x01, 0x59, 0x09, 0x06,
+	0x3E, 0x41, 0x5D, 0x59, 0x4E,
+	0x7C, 0x12, 0x11, 0x12, 0x7C,
+	0x7F, 0x49, 0x49, 0x49, 0x36,
+	0x3E, 0x41, 0x41, 0x41, 0x22,
+	0x7F, 0x41, 0x41, 0x41, 0x3E,
+	0x7F, 0x49, 0x49, 0x49, 0x41,
+	0x7F, 0x09, 0x09, 0x09, 0x01,
+	0x3E, 0x41, 0x41, 0x51, 0x73,
+	0x7F, 0x08, 0x08, 0x08, 0x7F,
+	0x00, 0x41, 0x7F, 0x41, 0x00,
+	0x20, 0x40, 0x41, 0x3F, 0x01,
+	0x7F, 0x08, 0x14, 0x22, 0x41,
+	0x7F, 0x40, 0x40, 0x40, 0x40,
+	0x7F, 0x02, 0x1C, 0x02, 0x7F,
+	0x7F, 0x04, 0x08, 0x10, 0x7F,
+	0x3E, 0x41, 0x41, 0x41, 0x3E,
+	0x7F, 0x09, 0x09, 0x09, 0x06,
+	0x3E, 0x41, 0x51, 0x21, 0x5E,
+	0x7F, 0x09, 0x19, 0x29, 0x46,
+	0x26, 0x49, 0x49, 0x49, 0x32,
+	0x03, 0x01, 0x7F, 0x01, 0x03,
+	0x3F, 0x40, 0x40, 0x40, 0x3F,
+	0x1F, 0x20, 0x40, 0x20, 0x1F,
+	0x3F, 0x40, 0x38, 0x40, 0x3F,
+	0x63, 0x14, 0x08, 0x14, 0x63,
+	0x03, 0x04, 0x78, 0x04, 0x03,
+	0x61, 0x59, 0x49, 0x4D, 0x43,
+	0x00, 0x7F, 0x41, 0x41, 0x41,
+	0x02, 0x04, 0x08, 0x10, 0x20,
+	0x00, 0x41, 0x41, 0x41, 0x7F,
+	0x04, 0x02, 0x01, 0x02, 0x04,
+	0x40, 0x40, 0x40, 0x40, 0x40,
+	0x00, 0x03, 0x07, 0x08, 0x00,
+	0x20, 0x54, 0x54, 0x78, 0x40,
+	0x7F, 0x28, 0x44, 0x44, 0x38,
+	0x38, 0x44, 0x44, 0x44, 0x28,
+	0x38, 0x44, 0x44, 0x28, 0x7F,
+	0x38, 0x54, 0x54, 0x54, 0x18,
+	0x00, 0x08, 0x7E, 0x09, 0x02,
+	0x18, 0xA4, 0xA4, 0x9C, 0x78,
+	0x7F, 0x08, 0x04, 0x04, 0x78,
+	0x00, 0x44, 0x7D, 0x40, 0x00,
+	0x20, 0x40, 0x40, 0x3D, 0x00,
+	0x7F, 0x10, 0x28, 0x44, 0x00,
+	0x00, 0x41, 0x7F, 0x40, 0x00,
+	0x7C, 0x04, 0x78, 0x04, 0x78,
+	0x7C, 0x08, 0x04, 0x04, 0x78,
+	0x38, 0x44, 0x44, 0x44, 0x38,
+	0xFC, 0x18, 0x24, 0x24, 0x18,
+	0x18, 0x24, 0x24, 0x18, 0xFC,
+	0x7C, 0x08, 0x04, 0x04, 0x08,
+	0x48, 0x54, 0x54, 0x54, 0x24,
+	0x04, 0x04, 0x3F, 0x44, 0x24,
+	0x3C, 0x40, 0x40, 0x20, 0x7C,
+	0x1C, 0x20, 0x40, 0x20, 0x1C,
+	0x3C, 0x40, 0x30, 0x40, 0x3C,
+	0x44, 0x28, 0x10, 0x28, 0x44,
+	0x4C, 0x90, 0x90, 0x90, 0x7C,
+	0x44, 0x64, 0x54, 0x4C, 0x44,
+	0x00, 0x08, 0x36, 0x41, 0x00,
+	0x00, 0x00, 0x77, 0x00, 0x00,
+	0x00, 0x41, 0x36, 0x08, 0x00,
+	0x02, 0x01, 0x02, 0x04, 0x02,
+	0x3C, 0x26, 0x23, 0x26, 0x3C,
+	0x1E, 0xA1, 0xA1, 0x61, 0x12,
+	0x3A, 0x40, 0x40, 0x20, 0x7A,
+	0x38, 0x54, 0x54, 0x55, 0x59,
+	0x21, 0x55, 0x55, 0x79, 0x41,
+	0x22, 0x54, 0x54, 0x78, 0x42, // a-umlaut
+	0x21, 0x55, 0x54, 0x78, 0x40,
+	0x20, 0x54, 0x55, 0x79, 0x40,
+	0x0C, 0x1E, 0x52, 0x72, 0x12,
+	0x39, 0x55, 0x55, 0x55, 0x59,
+	0x39, 0x54, 0x54, 0x54, 0x59,
+	0x39, 0x55, 0x54, 0x54, 0x58,
+	0x00, 0x00, 0x45, 0x7C, 0x41,
+	0x00, 0x02, 0x45, 0x7D, 0x42,
+	0x00, 0x01, 0x45, 0x7C, 0x40,
+	0x7D, 0x12, 0x11, 0x12, 0x7D, // A-umlaut
+	0xF0, 0x28, 0x25, 0x28, 0xF0,
+	0x7C, 0x54, 0x55, 0x45, 0x00,
+	0x20, 0x54, 0x54, 0x7C, 0x54,
+	0x7C, 0x0A, 0x09, 0x7F, 0x49,
+	0x32, 0x49, 0x49, 0x49, 0x32,
+	0x3A, 0x44, 0x44, 0x44, 0x3A, // o-umlaut
+	0x32, 0x4A, 0x48, 0x48, 0x30,
+	0x3A, 0x41, 0x41, 0x21, 0x7A,
+	0x3A, 0x42, 0x40, 0x20, 0x78,
+	0x00, 0x9D, 0xA0, 0xA0, 0x7D,
+	0x3D, 0x42, 0x42, 0x42, 0x3D, // O-umlaut
+	0x3D, 0x40, 0x40, 0x40, 0x3D,
+	0x3C, 0x24, 0xFF, 0x24, 0x24,
+	0x48, 0x7E, 0x49, 0x43, 0x66,
+	0x2B, 0x2F, 0xFC, 0x2F, 0x2B,
+	0xFF, 0x09, 0x29, 0xF6, 0x20,
+	0xC0, 0x88, 0x7E, 0x09, 0x03,
+	0x20, 0x54, 0x54, 0x79, 0x41,
+	0x00, 0x00, 0x44, 0x7D, 0x41,
+	0x30, 0x48, 0x48, 0x4A, 0x32,
+	0x38, 0x40, 0x40, 0x22, 0x7A,
+	0x00, 0x7A, 0x0A, 0x0A, 0x72,
+	0x7D, 0x0D, 0x19, 0x31, 0x7D,
+	0x26, 0x29, 0x29, 0x2F, 0x28,
+	0x26, 0x29, 0x29, 0x29, 0x26,
+	0x30, 0x48, 0x4D, 0x40, 0x20,
+	0x38, 0x08, 0x08, 0x08, 0x08,
+	0x08, 0x08, 0x08, 0x08, 0x38,
+	0x2F, 0x10, 0xC8, 0xAC, 0xBA,
+	0x2F, 0x10, 0x28, 0x34, 0xFA,
+	0x00, 0x00, 0x7B, 0x00, 0x00,
+	0x08, 0x14, 0x2A, 0x14, 0x22,
+	0x22, 0x14, 0x2A, 0x14, 0x08,
+	0x55, 0x00, 0x55, 0x00, 0x55, // #176 (25% block) missing in old code
+	0xAA, 0x55, 0xAA, 0x55, 0xAA, // 50% block
+	0xFF, 0x55, 0xFF, 0x55, 0xFF, // 75% block
+	0x00, 0x00, 0x00, 0xFF, 0x00,
+	0x10, 0x10, 0x10, 0xFF, 0x00,
+	0x14, 0x14, 0x14, 0xFF, 0x00,
+	0x10, 0x10, 0xFF, 0x00, 0xFF,
+	0x10, 0x10, 0xF0, 0x10, 0xF0,
+	0x14, 0x14, 0x14, 0xFC, 0x00,
+	0x14, 0x14, 0xF7, 0x00, 0xFF,
+	0x00, 0x00, 0xFF, 0x00, 0xFF,
+	0x14, 0x14, 0xF4, 0x04, 0xFC,
+	0x14, 0x14, 0x17, 0x10, 0x1F,
+	0x10, 0x10, 0x1F, 0x10, 0x1F,
+	0x14, 0x14, 0x14, 0x1F, 0x00,
+	0x10, 0x10, 0x10, 0xF0, 0x00,
+	0x00, 0x00, 0x00, 0x1F, 0x10,
+	0x10, 0x10, 0x10, 0x1F, 0x10,
+	0x10, 0x10, 0x10, 0xF0, 0x10,
+	0x00, 0x00, 0x00, 0xFF, 0x10,
+	0x10, 0x10, 0x10, 0x10, 0x10,
+	0x10, 0x10, 0x10, 0xFF, 0x10,
+	0x00, 0x00, 0x00, 0xFF, 0x14,
+	0x00, 0x00, 0xFF, 0x00, 0xFF,
+	0x00, 0x00, 0x1F, 0x10, 0x17,
+	0x00, 0x00, 0xFC, 0x04, 0xF4,
+	0x14, 0x14, 0x17, 0x10, 0x17,
+	0x14, 0x14, 0xF4, 0x04, 0xF4,
+	0x00, 0x00, 0xFF, 0x00, 0xF7,
+	0x14, 0x14, 0x14, 0x14, 0x14,
+	0x14, 0x14, 0xF7, 0x00, 0xF7,
+	0x14, 0x14, 0x14, 0x17, 0x14,
+	0x10, 0x10, 0x1F, 0x10, 0x1F,
+	0x14, 0x14, 0x14, 0xF4, 0x14,
+	0x10, 0x10, 0xF0, 0x10, 0xF0,
+	0x00, 0x00, 0x1F, 0x10, 0x1F,
+	0x00, 0x00, 0x00, 0x1F, 0x14,
+	0x00, 0x00, 0x00, 0xFC, 0x14,
+	0x00, 0x00, 0xF0, 0x10, 0xF0,
+	0x10, 0x10, 0xFF, 0x10, 0xFF,
+	0x14, 0x14, 0x14, 0xFF, 0x14,
+	0x10, 0x10, 0x10, 0x1F, 0x00,
+	0x00, 0x00, 0x00, 0xF0, 0x10,
+	0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+	0xF0, 0xF0, 0xF0, 0xF0, 0xF0,
+	0xFF, 0xFF, 0xFF, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0xFF, 0xFF,
+	0x0F, 0x0F, 0x0F, 0x0F, 0x0F,
+	0x38, 0x44, 0x44, 0x38, 0x44,
+	0xFC, 0x4A, 0x4A, 0x4A, 0x34, // sharp-s or beta
+	0x7E, 0x02, 0x02, 0x06, 0x06,
+	0x02, 0x7E, 0x02, 0x7E, 0x02,
+	0x63, 0x55, 0x49, 0x41, 0x63,
+	0x38, 0x44, 0x44, 0x3C, 0x04,
+	0x40, 0x7E, 0x20, 0x1E, 0x20,
+	0x06, 0x02, 0x7E, 0x02, 0x02,
+	0x99, 0xA5, 0xE7, 0xA5, 0x99,
+	0x1C, 0x2A, 0x49, 0x2A, 0x1C,
+	0x4C, 0x72, 0x01, 0x72, 0x4C,
+	0x30, 0x4A, 0x4D, 0x4D, 0x30,
+	0x30, 0x48, 0x78, 0x48, 0x30,
+	0xBC, 0x62, 0x5A, 0x46, 0x3D,
+	0x3E, 0x49, 0x49, 0x49, 0x00,
+	0x7E, 0x01, 0x01, 0x01, 0x7E,
+	0x2A, 0x2A, 0x2A, 0x2A, 0x2A,
+	0x44, 0x44, 0x5F, 0x44, 0x44,
+	0x40, 0x51, 0x4A, 0x44, 0x40,
+	0x40, 0x44, 0x4A, 0x51, 0x40,
+	0x00, 0x00, 0xFF, 0x01, 0x03,
+	0xE0, 0x80, 0xFF, 0x00, 0x00,
+	0x08, 0x08, 0x6B, 0x6B, 0x08,
+	0x36, 0x12, 0x36, 0x24, 0x36,
+	0x06, 0x0F, 0x09, 0x0F, 0x06,
+	0x00, 0x00, 0x18, 0x18, 0x00,
+	0x00, 0x00, 0x10, 0x10, 0x00,
+	0x30, 0x40, 0xFF, 0x01, 0x01,
+	0x00, 0x1F, 0x01, 0x01, 0x1E,
+	0x00, 0x19, 0x1D, 0x17, 0x12,
+	0x00, 0x3C, 0x3C, 0x3C, 0x3C,
+	0x00, 0x00, 0x00, 0x00, 0x00  // #255 NBSP
+};
+#endif // FONT5X7_H
diff --git a/keyboards/lets_split/i2c.h b/keyboards/lets_split/i2c.h
index 08ce4b0093..c15b6bc506 100644
--- a/keyboards/lets_split/i2c.h
+++ b/keyboards/lets_split/i2c.h
@@ -16,7 +16,7 @@
 #define SLAVE_BUFFER_SIZE 0x10
 
 // i2c SCL clock frequency
-#define SCL_CLOCK  100000L
+#define SCL_CLOCK  400000L
 
 extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
 
@@ -28,4 +28,22 @@ uint8_t i2c_master_read(int);
 void i2c_reset_state(void);
 void i2c_slave_init(uint8_t address);
 
+
+static inline unsigned char i2c_start_read(unsigned char addr) {
+  return i2c_master_start((addr << 1) | I2C_READ);
+}
+
+static inline unsigned char i2c_start_write(unsigned char addr) {
+  return i2c_master_start((addr << 1) | I2C_WRITE);
+}
+
+// from SSD1306 scrips
+extern unsigned char i2c_rep_start(unsigned char addr);
+extern void i2c_start_wait(unsigned char addr);
+extern unsigned char i2c_readAck(void);
+extern unsigned char i2c_readNak(void);
+extern unsigned char i2c_read(unsigned char ack);
+
+#define i2c_read(ack)  (ack) ? i2c_readAck() : i2c_readNak();
+
 #endif
diff --git a/keyboards/lets_split/keymaps/OLED_sample/Makefile b/keyboards/lets_split/keymaps/OLED_sample/Makefile
new file mode 100644
index 0000000000..90616d1f19
--- /dev/null
+++ b/keyboards/lets_split/keymaps/OLED_sample/Makefile
@@ -0,0 +1,25 @@
+
+# Build Options
+#   change to "no" to disable the options, or define them in the Makefile in 
+#   the appropriate keymap folder that will get included automatically
+#
+BOOTMAGIC_ENABLE = no       # Virtual DIP switch configuration(+1000)
+MOUSEKEY_ENABLE = yes       # Mouse keys(+4700)
+EXTRAKEY_ENABLE = yes       # Audio control and System control(+450)
+CONSOLE_ENABLE = no         # Console for debug(+400)
+COMMAND_ENABLE = no        # Commands for debug and configuration
+NKRO_ENABLE = yes            # Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+BACKLIGHT_ENABLE = no      # Enable keyboard backlight functionality
+MIDI_ENABLE = no            # MIDI controls
+AUDIO_ENABLE = no           # Audio output on port C6
+UNICODE_ENABLE = no         # Unicode
+BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
+RGBLIGHT_ENABLE = yes        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
+ONEHAND_ENABLE = no        # Enable one-hand typing
+
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
+
+ifndef QUANTUM_DIR
+	include ../../../../Makefile
+endif
\ No newline at end of file
diff --git a/keyboards/lets_split/keymaps/OLED_sample/config.h b/keyboards/lets_split/keymaps/OLED_sample/config.h
new file mode 100644
index 0000000000..8389ba111d
--- /dev/null
+++ b/keyboards/lets_split/keymaps/OLED_sample/config.h
@@ -0,0 +1,42 @@
+/*
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define USE_I2C
+//#define USE_SERIAL
+//#define MASTER_RIGHT
+#define FLIP_HALF
+
+#define SSD1306OLED
+
+
+#define PREVENT_STUCK_MODIFIERS
+#define TAPPING_FORCE_HOLD
+#define TAPPING_TERM 100
+
+#ifdef SUBPROJECT_rev1
+    #include "../../rev1/config.h"
+#endif
+#ifdef SUBPROJECT_rev2
+    #include "../../rev2/config.h"
+#endif
+
+#undef RGBLED_NUM
+#define RGBLIGHT_ANIMATIONS
+#define RGBLED_NUM 6
+#define RGBLIGHT_HUE_STEP 10
+#define RGBLIGHT_SAT_STEP 17
+#define RGBLIGHT_VAL_STEP 17
diff --git a/keyboards/lets_split/keymaps/OLED_sample/keymap.c b/keyboards/lets_split/keymaps/OLED_sample/keymap.c
new file mode 100644
index 0000000000..493ebcd3f2
--- /dev/null
+++ b/keyboards/lets_split/keymaps/OLED_sample/keymap.c
@@ -0,0 +1,359 @@
+#include "lets_split.h"
+#include "bootloader.h"
+#include "action_layer.h"
+#include "eeconfig.h"
+#include "tmk_core/protocol/lufa/LUFA-git/LUFA/Drivers/Peripheral/TWI.h"
+#ifdef AUDIO_ENABLE
+  #include "audio.h"
+#endif
+#ifdef SSD1306OLED
+  #include "ssd1306.h"
+#endif
+
+extern keymap_config_t keymap_config;
+
+//Following line allows macro to read current RGB settings
+extern rgblight_config_t rgblight_config;
+
+
+// Each layer gets a name for readability, which is then used in the keymap matrix below.
+// The underscores don't mean anything - you can have a layer called STUFF or any other name.
+// Layer names don't all need to be of the same length, obviously, and you can also skip them
+// entirely and just use numbers.
+#define _QWERTY 0
+#define _COLEMAK 1
+#define _DVORAK 2
+#define _LOWER 3
+#define _RAISE 4
+#define _ADJUST 16
+
+enum custom_keycodes {
+  QWERTY = SAFE_RANGE,
+  COLEMAK,
+  DVORAK,
+  LOWER,
+  RAISE,
+  ADJUST,
+  BACKLIT,
+  RGBLED_TOGGLE,
+  RGBLED_STEP_MODE,
+  RGBLED_INCREASE_HUE,
+  RGBLED_DECREASE_HUE,
+  RGBLED_INCREASE_SAT,
+  RGBLED_DECREASE_SAT,
+  RGBLED_INCREASE_VAL,
+  RGBLED_DECREASE_VAL,
+};
+
+enum macro_keycodes {
+  KC_SAMPLEMACRO,
+};
+
+
+// Fillers to make layering more clear
+#define _______ KC_TRNS
+#define XXXXXXX KC_NO
+//Macros
+#define M_SAMPLE M(KC_SAMPLEMACRO)
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+/* Qwerty
+ * ,-----------------------------------------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |   Y  |   U  |   I  |   O  |   P  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Esc  |   A  |   S  |   D  |   F  |   G  |   H  |   J  |   K  |   L  |   ;  |  "   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * | Shift|   Z  |   X  |   C  |   V  |   B  |   N  |   M  |   ,  |   .  |   /  |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |Adjust| Ctrl | Alt  | GUI  |Lower |Space |Space |Raise | Left | Down |  Up  |Right |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_QWERTY] = KEYMAP( \
+  KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_BSPC, \
+  KC_ESC,  KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, \
+  KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT , \
+  ADJUST,  KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT \
+),
+
+/* Colemak
+ * ,-----------------------------------------------------------------------------------.
+ * | Tab  |   Q  |   W  |   F  |   P  |   G  |   J  |   L  |   U  |   Y  |   ;  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Esc  |   A  |   R  |   S  |   T  |   D  |   H  |   N  |   E  |   I  |   O  |  "   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * | Shift|   Z  |   X  |   C  |   V  |   B  |   K  |   M  |   ,  |   .  |   /  |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |Adjust| Ctrl | Alt  | GUI  |Lower |Space |Space |Raise | Left | Down |  Up  |Right |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_COLEMAK] = KEYMAP( \
+  KC_TAB,  KC_Q,    KC_W,    KC_F,    KC_P,    KC_G,    KC_J,    KC_L,    KC_U,    KC_Y,    KC_SCLN, KC_BSPC, \
+  KC_ESC,  KC_A,    KC_R,    KC_S,    KC_T,    KC_D,    KC_H,    KC_N,    KC_E,    KC_I,    KC_O,    KC_QUOT, \
+  KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_K,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT , \
+  ADJUST,  KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT \
+),
+
+/* Dvorak
+ * ,-----------------------------------------------------------------------------------.
+ * | Tab  |   "  |   ,  |   .  |   P  |   Y  |   F  |   G  |   C  |   R  |   L  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Esc  |   A  |   O  |   E  |   U  |   I  |   D  |   H  |   T  |   N  |   S  |  /   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * | Shift|   ;  |   Q  |   J  |   K  |   X  |   B  |   M  |   W  |   V  |   Z  |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |Adjust| Ctrl | Alt  | GUI  |Lower |Space |Space |Raise | Left | Down |  Up  |Right |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_DVORAK] = KEYMAP( \
+  KC_TAB,  KC_QUOT, KC_COMM, KC_DOT,  KC_P,    KC_Y,    KC_F,    KC_G,    KC_C,    KC_R,    KC_L,    KC_BSPC, \
+  KC_ESC,  KC_A,    KC_O,    KC_E,    KC_U,    KC_I,    KC_D,    KC_H,    KC_T,    KC_N,    KC_S,    KC_SLSH, \
+  KC_LSFT, KC_SCLN, KC_Q,    KC_J,    KC_K,    KC_X,    KC_B,    KC_M,    KC_W,    KC_V,    KC_Z,    KC_ENT , \
+  ADJUST,  KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT \
+),
+
+/* Lower
+ * ,-----------------------------------------------------------------------------------.
+ * |   ~  |   !  |   @  |   #  |   $  |   %  |   ^  |   &  |   *  |   (  |   )  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Del  |  F1  |  F2  |  F3  |  F4  |  F5  |  F6  |   _  |   +  |     |    \  |  |   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |  F7  |  F8  |  F9  |  F10 |  F11 |  F12 |ISO ~ |ISO | |      |      |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      | Next | Vol- | Vol+ | Play |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_LOWER] = KEYMAP( \
+  KC_TILD, KC_EXLM, KC_AT,   KC_HASH, KC_DLR,  KC_PERC, KC_CIRC, KC_AMPR, KC_ASTR, KC_LPRN, KC_RPRN, KC_BSPC, \
+  KC_DEL,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_UNDS, KC_PLUS, KC_LCBR, KC_RCBR, KC_PIPE, \
+  _______, KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,S(KC_NUHS),S(KC_NUBS),_______, _______, _______, \
+  _______, _______, _______, _______, _______, _______, _______, _______, KC_MNXT, KC_VOLD, KC_VOLU, KC_MPLY \
+),
+
+/* Raise
+ * ,-----------------------------------------------------------------------------------.
+ * |   `  |   1  |   2  |   3  |   4  |   5  |   6  |   7  |   8  |   9  |   0  | Bksp |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * | Del  |  F1  |  F2  |  F3  |  F4  |  F5  |  F6  |   -  |   =  |   [  |   ]  |  \   |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |  F7  |  F8  |  F9  |  F10 |  F11 |  F12 |ISO # |ISO / |      |      |Enter |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      | Next | Vol- | Vol+ | Play |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_RAISE] = KEYMAP( \
+  KC_GRV,  KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_BSPC, \
+  KC_DEL,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_MINS, KC_EQL,  KC_LBRC, KC_RBRC, KC_BSLS, \
+  _______, KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  KC_NUHS, KC_NUBS, _______, _______, _______, \
+  _______, _______, _______, _______, _______, _______, _______, _______, KC_MNXT, KC_VOLD, KC_VOLU, KC_MPLY \
+),
+
+/* Adjust (Lower + Raise)
+ * ,-----------------------------------------------------------------------------------.
+ * |      | Reset|      |      |      |      |      |      |      |      |      |  Del |
+ * |------+------+------+------+------+-------------+------+------+------+------+------|
+ * |      |      |      |Aud on|Audoff|AGnorm|AGswap|Qwerty|Colemk|Dvorak|      |      |
+ * |------+------+------+------+------+------|------+------+------+------+------+------|
+ * |      |      |      |      |      |      |      |      |      |      |      |      |
+ * |------+------+------+------+------+------+------+------+------+------+------+------|
+ * |      |      |      |      |      |             |      |      |      |      |      |
+ * `-----------------------------------------------------------------------------------'
+ */
+[_ADJUST] =  KEYMAP( \
+  _______, RESET,   _______, M_SAMPLE, _______, _______, _______, _______, _______, _______, _______, KC_DEL, \
+  _______, _______, _______, AU_ON,   AU_OFF,  AG_NORM, AG_SWAP, QWERTY,  COLEMAK, DVORAK,  _______, _______, \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______ \
+)
+
+
+};
+
+
+#ifdef AUDIO_ENABLE
+
+float tone_startup[][2]    = SONG(STARTUP_SOUND);
+float tone_qwerty[][2]     = SONG(QWERTY_SOUND);
+float tone_dvorak[][2]     = SONG(DVORAK_SOUND);
+float tone_colemak[][2]    = SONG(COLEMAK_SOUND);
+float tone_plover[][2]     = SONG(PLOVER_SOUND);
+float tone_plover_gb[][2]  = SONG(PLOVER_GOODBYE_SOUND);
+float music_scale[][2]     = SONG(MUSIC_SCALE_SOUND);
+float tone_goodbye[][2]    = SONG(GOODBYE_SOUND);
+#endif
+
+// define variables for reactive RGB
+bool TOG_STATUS = false;
+int RGB_current_mode;
+
+void persistant_default_layer_set(uint16_t default_layer) {
+  eeconfig_update_default_layer(default_layer);
+  default_layer_set(default_layer);
+}
+
+// Setting ADJUST layer RGB back to default
+void update_tri_layer_RGB(uint8_t layer1, uint8_t layer2, uint8_t layer3) {
+  if (IS_LAYER_ON(layer1) && IS_LAYER_ON(layer2)) {
+    rgblight_mode(RGB_current_mode);
+    layer_on(layer3);
+  } else {
+    layer_off(layer3);
+  }
+}
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  switch (keycode) {
+    case QWERTY:
+      if (record->event.pressed) {
+        #ifdef AUDIO_ENABLE
+          PLAY_NOTE_ARRAY(tone_qwerty, false, 0);
+        #endif
+        persistant_default_layer_set(1UL<<_QWERTY);
+      }
+      return false;
+      break;
+    case COLEMAK:
+      if (record->event.pressed) {
+        #ifdef AUDIO_ENABLE
+          PLAY_NOTE_ARRAY(tone_colemak, false, 0);
+        #endif
+        persistant_default_layer_set(1UL<<_COLEMAK);
+      }
+      return false;
+      break;
+    case DVORAK:
+      if (record->event.pressed) {
+        #ifdef AUDIO_ENABLE
+          PLAY_NOTE_ARRAY(tone_dvorak, false, 0);
+        #endif
+        persistant_default_layer_set(1UL<<_DVORAK);
+      }
+      return false;
+      break;
+    case LOWER:
+      if (record->event.pressed) {
+          //not sure how to have keyboard check mode and set it to a variable, so my work around
+          //uses another variable that would be set to true after the first time a reactive key is pressed.
+        if (TOG_STATUS) { //TOG_STATUS checks is another reactive key currently pressed, only changes RGB mode if returns false
+        } else {
+          TOG_STATUS = !TOG_STATUS;
+          rgblight_mode(16);
+        }
+        layer_on(_LOWER);
+        update_tri_layer_RGB(_LOWER, _RAISE, _ADJUST);
+      } else {
+        rgblight_mode(RGB_current_mode);   // revert RGB to initial mode prior to RGB mode change
+        TOG_STATUS = false;
+        layer_off(_LOWER);
+        update_tri_layer_RGB(_LOWER, _RAISE, _ADJUST);
+      }
+      return false;
+      break;
+    case RAISE:
+      if (record->event.pressed) {
+        //not sure how to have keyboard check mode and set it to a variable, so my work around
+        //uses another variable that would be set to true after the first time a reactive key is pressed.
+        if (TOG_STATUS) { //TOG_STATUS checks is another reactive key currently pressed, only changes RGB mode if returns false
+        } else {
+          TOG_STATUS = !TOG_STATUS;
+          rgblight_mode(15);
+        }
+        layer_on(_RAISE);
+        update_tri_layer_RGB(_LOWER, _RAISE, _ADJUST);
+      } else {
+        rgblight_mode(RGB_current_mode);  // revert RGB to initial mode prior to RGB mode change
+        layer_off(_RAISE);
+        TOG_STATUS = false;
+        update_tri_layer_RGB(_LOWER, _RAISE, _ADJUST);
+      }
+      return false;
+      break;
+    case BACKLIT:
+      if (record->event.pressed) {
+        register_code(KC_RSFT);
+        #ifdef BACKLIGHT_ENABLE
+          backlight_step();
+        #endif
+      } else {
+        unregister_code(KC_RSFT);
+      }
+      return false;
+      break;
+      //led operations - RGB mode change now updates the RGB_current_mode to allow the right RGB mode to be set after reactive keys are released
+    case RGB_MOD:
+      if (record->event.pressed) {
+        rgblight_mode(RGB_current_mode);
+        rgblight_step();
+        RGB_current_mode = rgblight_config.mode;
+      }
+      return false;
+      break;
+  }
+  return true;
+}
+
+void matrix_init_user(void) {
+    #ifdef AUDIO_ENABLE
+        startup_user();
+    #endif
+    RGB_current_mode = rgblight_config.mode; 
+}
+
+//SSD1306 OLED init and update loop, make sure to add #define SSD1306OLED in config.h
+#ifdef SSD1306OLED
+void matrix_master_OLED_init (void) {
+    TWI_Init(TWI_BIT_PRESCALE_1, TWI_BITLENGTH_FROM_FREQ(1, 800000));
+    iota_gfx_init();   // turns on the display   
+}
+
+void matrix_scan_user(void) {
+     iota_gfx_task();  // this is what updates the display continuously
+}
+#endif
+
+#ifdef AUDIO_ENABLE
+
+void startup_user()
+{
+    _delay_ms(20); // gets rid of tick
+    PLAY_NOTE_ARRAY(tone_startup, false, 0);
+}
+
+void shutdown_user()
+{
+    PLAY_NOTE_ARRAY(tone_goodbye, false, 0);
+    _delay_ms(150);
+    stop_all_notes();
+}
+
+void music_on_user(void)
+{
+    music_scale_user();
+}
+
+void music_scale_user(void)
+{
+    PLAY_NOTE_ARRAY(music_scale, false, 0);
+}
+
+#endif
+
+/*
+ * Macro definition
+ */
+const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt)
+{
+    if (!eeconfig_is_enabled()) {
+      eeconfig_init();
+    }
+
+    switch (id) {
+      case KC_SAMPLEMACRO:
+        if (record->event.pressed){
+          return MACRO (I(10), T(H), T(E), T(L), T(L), T(O), T(SPACE), T(W), T(O), T(R), T(L), T(D), END);
+        }
+ 
+    }
+
+    return MACRO_NONE;
+}
diff --git a/keyboards/lets_split/keymaps/OLED_sample/readme.md b/keyboards/lets_split/keymaps/OLED_sample/readme.md
new file mode 100644
index 0000000000..02888855b8
--- /dev/null
+++ b/keyboards/lets_split/keymaps/OLED_sample/readme.md
@@ -0,0 +1,25 @@
+SSD1306 OLED Display via I2C
+======
+
+Features
+--------
+
+Some features supported by the firmware:
+
+
+* I2C connection between the two halves is required as the OLED display will use this connection as well. Note this
+  requires pull-up resistors on the data and clock lines.
+* OLED display will connect from either side
+
+
+Wiring
+------
+
+