[Keymap] Balance Twelve-based layout for Niu Mini (#5228)

* Balance Twelve-based layout for Niu Mini.

* niu - Changes following review.

* niu - Changes following review.

4 files changed, 247 insertions, 0 deletions

diff --git a/keyboards/niu_mini/keymaps/yttyx/README.md b/keyboards/niu_mini/keymaps/yttyx/README.md
new file mode 100644
index 0000000000..a48bdcca35
--- /dev/null
+++ b/keyboards/niu_mini/keymaps/yttyx/README.md
@@ -0,0 +1,92 @@
+# Overview
+
+This layout is based on Balance Twelve (mirror variant) by Sasha Viminitz. Please see [this page](https://mathematicalmulticore.wordpress.com/the-keyboard-layout-project/) 
+for more information. It's designed for left-handers who use their right hand for the mouse.
+
+## To build
+
+```
+make niu_mini:yttyx
+```
+
+## To flash (example)
+
+```
+sudo dfu-programmer atmega32u4 erase
+sudo dfu-programmer atmega32u4 flash niu_mini_yttyx.hex --debug 6
+sudo dfu-programmer atmega32u4 launch
+```
+
+## Layers
+
+### Base:
+
+    .--------.-------.-------.-------.--------.                           .-------.-------.-------.-------.------.
+    | P      | L     | C     | D     | W      |                           | U     | O     | Y     | K     | Q    |
+    |--------+-------+-------+-------+--------|                           |-------+-------+-------+-------+------|
+    | N      | R     | S     | T     | M      |                           | A     | E     | I     | H     | V    |
+    |--------+-------+-------+-------+--------|                           |-------+-------+-------+-------+------|
+    | Z Sft  | J Ctl | F Alt | G     | B      |                           | ,     | . Alt | ; Ctl | X Sft | Sup  |
+    '--------'-------'-------+-------+--------+-----.               .-----+-------+-------+-------'-------'------'
+                             | BS P1 | Spc P2 | P3  |               |     | Sft   |       |
+                             '-------'--------'-----'               '-----'-------'-------'
+
+### P1: Punctuation (1)
+
+    .--------.-------.-------.-------.-------.                              .------.-------.-------.-------.------.
+    | Esc    |       |       |       |       |                              | |    | /     | ^     | £     |  ~   |
+    |--------+-------+-------+-------+-------|                              |------+-------+-------+-------+------|
+    | Tab    |       |       |       |       |                              | &    | \     | `     | $     | Ent  |
+    |--------+-------+-------+-------+-------|                              |------+-------+-------+-------+------|
+    | Sft    | Ctl   | Alt   | Del   |       |                              | %    | Alt   | Ctl   | Sft   | Sup  |
+    '--------'-------'-------+-------+-------+-----.                  .-----+------+-------+-------'-------'------'
+                             | P1    |       |     |                  |     | Sft  |       |
+                             '-------'-------'-----'                  '-----'------'-------'
+
+### P2: Punctuation (2)
+
+    .-------.-------.-------.-------.-------.                               .-------.-------.-------.-------.------.
+    | Esc   |       | NC    | FV    |       |                               | (     | )     | "     | ?     |      |
+    |-------+-------+-------+-------+-------|                               |-------+-------+-------+-------+------|
+    | Tab   | Ctl-X | Ctl-C | Ctl-V | Ctl-Z |                               | {     | }     | '     | !     | Ent  |
+    |-------+-------+-------+-------+-------|                               |-------+-------+-------+-------+------|
+    | Sft   | Ctl   | Alt   | Del   | Ent   |                               | #     | Alt   | Ctl   | Sft   | Sup  |
+    '-------'-------'-------+-------+-------+-----.                   .-----+-------+-------+-------'-------'------'
+                            | BS    | P2    |     |                   |     | Sft   |       |
+                            '-------'-------'-----'                   '-----'-------'-------'
+
+### P3: Punctuation (3)
+
+    .-------.-------.-------.-------.-------.                             .------.-------.-------.-------.------.
+    | Esc   |       | Break | Pscr  | ScLk  |                             | <    | >     | +     | _     | =    |
+    |-------+-------+-------+-------+-------|                             |------+-------+-------+-------+------|
+    | Tab   |       |       | Caps  |       |                             | [    | ]     | *     | -     | Ent  |
+    |-------+-------+-------+-------+-------|                             |------+-------+-------+-------+------|
+    | Sft   | Ctl   | Alt   | Del   |       |                             | @    | Alt   | Ctl   | Sft   | Sup  |
+    '-------'-------'-------+-------+-------+-----.                 .-----+------+-------+-------'-------'------'
+                            | BS    |       | P3  |                 |     | Sft  |       |
+                            '-------'-------'-----'                 '-----'------'-------'
+
+### Numerals / Cursor control
+
+    .-------.-------.-------.------.-------.                              .------.-------.-------.------.------.
+    | 1     | 2     | 3     | 4    | 5     |                              | Home | Up    | End   | PgUp |      |
+    |-------+-------+-------+------+-------|                              |------+-------+-------+------+------|
+    | 6     | 7     | 8     | 9    | 0     |                              | Left | Down  | Right | PgDn |      |
+    |-------+-------+-------+------+-------|                              |------+-------+-------+------+------|
+    | Sft   | Ctl   | Alt   | Del  | .     |                              | Ins  | Alt   | Ctl   | Sft  | Sup  |
+    '-------'-------'-------+------+-------+-----.                  .-----+------+-------+-------'------'------'
+                            | BS   | BA    |     |                  |     | Sft  |       |
+                            '------'-------'-----'                  '-----'------'-------'
+
+### FV: Function keys / Cursor control (Vim)
+
+    .-------.------.-------.-----.-------.                                .------.-------.-----.-------.------.
+    | F1    | F2   | F3    | F4  | F5    |                                | 0    | K     | $   | Ctl-B |      |
+    |-------+------+-------+-----+-------|                                |------+-------+-----+-------+------|
+    | F6    | F7   | F8    | F9  | F10   |                                | H    | J     | L   | Ctl-F |      |
+    |-------+------+-------+-----+-------|                                |------+-------+-----+-------+------|
+    | Sft   | Ctl  | Alt   | F11 | F12   |                                |      | Alt   | Ctl | Sft   | Sup  |
+    '-------'------'-------+-----+-------+-----.                    .-----+------+-------+-----'-------'------'
+                           | BS  | BA    |     |                    |     | Sft  |       |
+                           '-----'-------'-----'                    '-----'------'-------'
diff --git a/keyboards/niu_mini/keymaps/yttyx/config.h b/keyboards/niu_mini/keymaps/yttyx/config.h
new file mode 100644
index 0000000000..b9e113ec0b
--- /dev/null
+++ b/keyboards/niu_mini/keymaps/yttyx/config.h
@@ -0,0 +1,4 @@
+#pragma once
+#define NO_ACTION_ONESHOT
+#define NO_ACTION_MACRO
+#define NO_ACTION_FUNCTION
diff --git a/keyboards/niu_mini/keymaps/yttyx/keymap.c b/keyboards/niu_mini/keymaps/yttyx/keymap.c
new file mode 100644
index 0000000000..6a9398dff9
--- /dev/null
+++ b/keyboards/niu_mini/keymaps/yttyx/keymap.c
@@ -0,0 +1,141 @@
+
+#include QMK_KEYBOARD_H
+
+enum layers {
+  BA,           // Base        (Balance Twelve mirror varian)
+  P1,           // Punctuation (1)
+  P2,           // Punctuation (2)
+  P3,           // Punctuation (2)
+  NC,           // Numerals / Cursor control
+  FV            // Function keys / Cursor control (Vim)
+};
+
+// Abbreviations - base
+#define KX_P1_BSPC      LT(P1, KC_BSPC)
+#define KX_P2_SPC       LT(P2, KC_SPC)
+
+#define KX_SFT_Z        MT(MOD_LSFT, KC_Z)
+#define KX_CTL_J        MT(MOD_LCTL, KC_J)
+#define KX_ALT_F        MT(MOD_LALT, KC_F)
+
+#define KX_ALT_DOT      MT(MOD_LALT, KC_DOT)
+#define KX_CTL_SCLN     MT(MOD_LCTL, KC_SCLN)
+#define KX_SFT_X        MT(MOD_LSFT, KC_X)
+
+#define KX_AT           LSFT(KC_QUOT)
+#define KX_DQUOT        LSFT(KC_2)
+#define KX_PIPE         LSFT(KC_NUBS)
+#define KX_TILDA        LSFT(KC_NUHS)
+
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  /*
+    .--------.-------.-------.-------.--------.                           .-------.-------.-------.-------.------.
+    | P      | L     | C     | D     | W      |                           | U     | O     | Y     | K     | Q    |
+    |--------+-------+-------+-------+--------|                           |-------+-------+-------+-------+------|
+    | N      | R     | S     | T     | M      |                           | A     | E     | I     | H     | V    |
+    |--------+-------+-------+-------+--------|                           |-------+-------+-------+-------+------|
+    | Z Sft  | J Ctl | F Alt | G     | B      |                           | ,     | . Alt | ; Ctl | X Sft | Sup  |
+    '--------'-------'-------+-------+--------+-----.               .-----+-------+-------+-------'-------'------'
+                             | BS P1 | Spc P2 | P3  |               |     | Sft   |       |
+                             '-------'--------'-----'               '-----'-------'-------'
+  */                                                               
+  [BA] = LAYOUT(                                                   
+    KC_P,     KC_L,     KC_C,     KC_D,       KC_W,      XXXXXXX,   XXXXXXX, KC_U,    KC_O,       KC_Y,        KC_K,     KC_Q,
+    KC_N,     KC_R,     KC_S,     KC_T,       KC_M,      XXXXXXX,   XXXXXXX, KC_A,    KC_E,       KC_I,        KC_H,     KC_V,
+    KX_SFT_Z, KX_CTL_J, KX_ALT_F, KC_G,       KC_B,      XXXXXXX,   XXXXXXX, KC_COMM, KX_ALT_DOT, KX_CTL_SCLN, KX_SFT_X, KC_LGUI,
+    XXXXXXX,  XXXXXXX,  XXXXXXX,  KX_P1_BSPC, KX_P2_SPC, MO(P3),    XXXXXXX, KC_RSFT, XXXXXXX,    XXXXXXX,     XXXXXXX,  XXXXXXX
+  ),
+
+  /* P1: Punctuation (1)
+    .--------.-------.-------.-------.-------.                              .------.-------.-------.-------.------.
+    | Esc    |       |       |       |       |                              | |    | /     | ^     | £     |  ~   |
+    |--------+-------+-------+-------+-------|                              |------+-------+-------+-------+------|
+    | Tab    |       |       |       |       |                              | &    | \     | `     | $     | Ent  |
+    |--------+-------+-------+-------+-------|                              |------+-------+-------+-------+------|
+    | Sft    | Ctl   | Alt   | Del   |       |                              | %    | Alt   | Ctl   | Sft   | Sup  |
+    '--------'-------'-------+-------+-------+-----.                  .-----+------+-------+-------'-------'------'
+                             | P1    |       |     |                  |     | Sft  |       |
+                             '-------'-------'-----'                  '-----'------'-------'
+  */
+  [P1] = LAYOUT(       
+    KC_ESC,  XXXXXXX,    XXXXXXX,    XXXXXXX,    XXXXXXX,    XXXXXXX, XXXXXXX, KX_PIPE, KC_SLSH, KC_CIRC, KC_HASH, KX_TILDA,  
+    KC_TAB,  XXXXXXX,    XXXXXXX,    XXXXXXX,    XXXXXXX,    XXXXXXX, XXXXXXX, KC_AMPR, KC_NUBS, KC_GRV,  KC_DLR,  KC_ENT,
+    KC_LSFT, KC_LCTL,    KC_LALT,    KC_DEL,     XXXXXXX,    XXXXXXX, XXXXXXX, KC_PERC, KC_LALT, KC_LCTL, KC_LSFT, _______,
+    XXXXXXX, XXXXXXX,    XXXXXXX,    _______,    XXXXXXX,    XXXXXXX, XXXXXXX, _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX
+  ),
+
+  /* P2: Punctuation (2)
+    .-------.-------.-------.-------.-------.                               .-------.-------.-------.-------.------.
+    | Esc   |       | NC    | FV    |       |                               | (     | )     | "     | ?     |      |
+    |-------+-------+-------+-------+-------|                               |-------+-------+-------+-------+------|
+    | Tab   | Ctl-X | Ctl-C | Ctl-V | Ctl-Z |                               | {     | }     | '     | !     | Ent  |
+    |-------+-------+-------+-------+-------|                               |-------+-------+-------+-------+------|
+    | Sft   | Ctl   | Alt   | Del   | Ent   |                               | #     | Alt   | Ctl   | Sft   | Sup  |
+    '-------'-------'-------+-------+-------+-----.                   .-----+-------+-------+-------'-------'------'
+                            | BS    | P2    |     |                   |     | Sft   |       |
+                            '-------'-------'-----'                   '-----'-------'-------'
+  */
+  [P2] = LAYOUT(
+    KC_ESC,  XXXXXXX,    TO(NC),     TO(FV),     XXXXXXX,    XXXXXXX, XXXXXXX, KC_LPRN, KC_RPRN, KX_DQUOT, KC_QUES, XXXXXXX,
+    KC_TAB,  LCTL(KC_X), LCTL(KC_C), LCTL(KC_V), LCTL(KC_Z), XXXXXXX, XXXXXXX, KC_LCBR, KC_RCBR, KC_QUOT,  KC_EXLM, KC_ENT,
+    KC_LSFT, KC_LCTL,    KC_LALT,    KC_DEL,     KC_ENT,     XXXXXXX, XXXXXXX, KC_NUHS, KC_LALT, KC_LCTL,  KC_LSFT, _______,
+    XXXXXXX, XXXXXXX,    XXXXXXX,    KC_BSPC,    _______,    XXXXXXX, XXXXXXX, _______, XXXXXXX, XXXXXXX,  XXXXXXX, XXXXXXX
+  ),
+
+  /* P3: Punctuation (3)
+    .-------.-------.-------.-------.-------.                             .------.-------.-------.-------.------.
+    | Esc   |       | Break | Pscr  | ScLk  |                             | <    | >     | +     | _     | =    |
+    |-------+-------+-------+-------+-------|                             |------+-------+-------+-------+------|
+    | Tab   |       |       | Caps  |       |                             | [    | ]     | *     | -     | Ent  |
+    |-------+-------+-------+-------+-------|                             |------+-------+-------+-------+------|
+    | Sft   | Ctl   | Alt   | Del   |       |                             | @    | Alt   | Ctl   | Sft   | Sup  |
+    '-------'-------'-------+-------+-------+-----.                 .-----+------+-------+-------'-------'------'
+                            | BS    |       | P3  |                 |     | Sft  |       |
+                            '-------'-------'-----'                 '-----'------'-------'
+  */
+  [P3] = LAYOUT(
+    KC_ESC,  XXXXXXX, KC_BRK,  KC_PSCR, KC_SLCK, XXXXXXX,           XXXXXXX, KC_LABK, KC_RABK, KC_PLUS, KC_UNDS, KC_EQL,
+    KC_TAB,  XXXXXXX, XXXXXXX, KC_CAPS, XXXXXXX, XXXXXXX,           XXXXXXX, KC_LBRC, KC_RBRC, KC_ASTR, KC_MINS, KC_ENT,
+    KC_LSFT, KC_LCTL, KC_LALT, KC_DEL,  XXXXXXX, XXXXXXX,           XXXXXXX, KX_AT,   KC_LALT, KC_LCTL, KC_LSFT, _______,
+    XXXXXXX, XXXXXXX, XXXXXXX, KC_BSPC, XXXXXXX, _______,           XXXXXXX, _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX
+  ),
+
+  /* NC: Numerals / Cursor control
+    .-------.-------.-------.------.-------.                              .------.-------.-------.------.------.
+    | 1     | 2     | 3     | 4    | 5     |                              | Home | Up    | End   | PgUp |      |
+    |-------+-------+-------+------+-------|                              |------+-------+-------+------+------|
+    | 6     | 7     | 8     | 9    | 0     |                              | Left | Down  | Right | PgDn |      |
+    |-------+-------+-------+------+-------|                              |------+-------+-------+------+------|
+    | Sft   | Ctl   | Alt   | Del  | .     |                              | Ins  | Alt   | Ctl   | Sft  | Sup  |
+    '-------'-------'-------+------+-------+-----.                  .-----+------+-------+-------'------'------'
+                            | BS   | BA    |     |                  |     | Sft  |       |
+                            '------'-------'-----'                  '-----'------'-------'
+  */
+  [NC] = LAYOUT(
+    KC_1,    KC_2,    KC_3,    KC_4,    KC_5,   XXXXXXX,            XXXXXXX, KC_HOME, KC_UP,   KC_END,  KC_PGUP, XXXXXXX,
+    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,   XXXXXXX,            XXXXXXX, KC_LEFT, KC_DOWN, KC_RGHT, KC_PGDN, XXXXXXX,
+    KC_LSFT, KC_LCTL, KC_LALT, KC_DEL,  KC_DOT, XXXXXXX,            XXXXXXX, KC_INS,  KC_LALT, KC_LCTL, KC_LSFT, _______,
+    XXXXXXX, XXXXXXX, XXXXXXX, KC_BSPC, TO(BA), XXXXXXX,            XXXXXXX, _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX
+  ),
+
+  /* FV: Function keys / Cursor control (Vim)
+    .-------.------.-------.-----.-------.                                .------.-------.-----.-------.------.
+    | F1    | F2   | F3    | F4  | F5    |                                | 0    | K     | $   | Ctl-B |      |
+    |-------+------+-------+-----+-------|                                |------+-------+-----+-------+------|
+    | F6    | F7   | F8    | F9  | F10   |                                | H    | J     | L   | Ctl-F |      |
+    |-------+------+-------+-----+-------|                                |------+-------+-----+-------+------|
+    | Sft   | Ctl  | Alt   | F11 | F12   |                                |      | Alt   | Ctl | Sft   | Sup  |
+    '-------'------'-------+-----+-------+-----.                    .-----+------+-------+-----'-------'------'
+                           | BS  | BA    |     |                    |     | Sft  |       |
+                           '-----'-------'-----'                    '-----'------'-------'
+  */
+  [FV] = LAYOUT(
+    KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,  XXXXXXX,            XXXXXXX, KC_0,    KC_K,    KC_DLR,   LCTL(KC_B), XXXXXXX,
+    KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10, XXXXXXX,            XXXXXXX, KC_H,    KC_J,    KC_L,     LCTL(KC_F), XXXXXXX,
+    KC_LSFT, KC_LCTL, KC_LALT, KC_F11,  KC_F12, XXXXXXX,            XXXXXXX, XXXXXXX, KC_LALT, KC_LCTL,  KC_LSFT,    _______,
+    XXXXXXX, XXXXXXX, XXXXXXX, KC_BSPC, TO(BA), XXXXXXX,            XXXXXXX, _______, XXXXXXX, XXXXXXX,  XXXXXXX,    XXXXXXX
+  )
+
+};
+
diff --git a/keyboards/niu_mini/keymaps/yttyx/rules.mk b/keyboards/niu_mini/keymaps/yttyx/rules.mk
new file mode 100644
index 0000000000..d8b21aa842
--- /dev/null
+++ b/keyboards/niu_mini/keymaps/yttyx/rules.mk
@@ -0,0 +1,10 @@
+# Build Options
+AUDIO_ENABLE = no
+CONSOLE_ENABLE = no
+EXTRAKEY_ENABLE = no
+MIDI_ENABLE = no
+MOUSEKEY_ENABLE = no
+NKRO_ENABLE = yes
+RGBLIGHT_ENABLE = no
+STENO_ENABLE = no
+VIRTSER_ENABLE = no