[Keyboard] hexon38 and Dual-role key implementation (#4709)

* initial dual-role key implementation for hexon38

* PR feedback, adding README

* Moving to handwired subdir

* Additional PR feedback

keyboards/handwired/hexon38/config.h

@@ -0,0 +1,60 @@
+// see https://github.com/pepaslabs/hexon38
+
+#pragma once
+
+#include "config_common.h"
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID       0xFEED
+#define PRODUCT_ID      0x6060
+#define DEVICE_VER      0x0001
+#define MANUFACTURER    pepaslabs
+#define PRODUCT         hexon38
+#define DESCRIPTION     "A handmade non-split ergonomic 38-key keyboard, inspired by the lil38.  See https://github.com/pepaslabs/hexon38."
+
+/* key matrix size */
+#define MATRIX_ROWS 4
+#define MATRIX_COLS 12
+
+/* key matrix pins */
+#define MATRIX_ROW_PINS { B0, F0, B2, F4 }
+#define MATRIX_COL_PINS { C6, D3, D2, D1, D0, B7, F6, F7, B6, B5, B4, D7 }
+#define UNUSED_PINS
+
+/* COL2ROW or ROW2COL */
+#define DIODE_DIRECTION ROW2COL
+
+/* number of backlight levels */
+
+#ifdef BACKLIGHT_PIN
+#define BACKLIGHT_LEVELS 0
+#endif
+
+/* Set 0 if debouncing isn't needed */
+#define DEBOUNCING_DELAY 5
+
+
+/* key combination for command */
+#define IS_COMMAND() ( \
+    keyboard_report->mods == (MOD_BIT(KC_LSHIFT) | MOD_BIT(KC_RSHIFT)) \
+)
+
+#ifdef RGB_DI_PIN
+#define RGBLIGHT_ANIMATIONS
+#define RGBLED_NUM 0
+#define RGBLIGHT_HUE_STEP 8
+#define RGBLIGHT_SAT_STEP 8
+#define RGBLIGHT_VAL_STEP 8
+#endif
+
+
+// Disabled features:
+
+/* Mechanical locking support. Use KC_LCAP, KC_LNUM or KC_LSCR instead in keymap */
+//#define LOCKING_SUPPORT_ENABLE
+
+/* Locking resynchronize hack */
+//#define LOCKING_RESYNC_ENABLE
+
+/* prevent stuck modifiers */
+//#define PREVENT_STUCK_MODIFIERS