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authorRobert Mills <robcmills@gmail.com>2023-03-07 10:13:46 -0800
committerGitHub <noreply@github.com>2023-03-07 10:13:46 -0800
commit8812db1d64d8927a23fdca49dd2409e090998e35 (patch)
treed1e0850e9fde158c1ece710fe13c3bfefcf12bfb /keyboards/karn
parente6e11dfde77a82d197f30289ca6bff8d3921a439 (diff)
[Keyboard] Add Karn Keyboard (#19846)
Co-authored-by: jack <0x6a73@protonmail.com> Co-authored-by: Joel Challis <git@zvecr.com> Co-authored-by: Drashna Jaelre <drashna@live.com>
Diffstat (limited to 'keyboards/karn')
-rw-r--r--keyboards/karn/config.h18
-rw-r--r--keyboards/karn/halconf.h8
-rw-r--r--keyboards/karn/info.json75
-rw-r--r--keyboards/karn/keymaps/colemak/config.h13
-rw-r--r--keyboards/karn/keymaps/colemak/keymap.c96
-rw-r--r--keyboards/karn/keymaps/colemak/readme.md58
-rw-r--r--keyboards/karn/keymaps/colemak/rules.mk1
-rw-r--r--keyboards/karn/keymaps/default/keymap.c41
-rw-r--r--keyboards/karn/mcuconf.h9
-rw-r--r--keyboards/karn/readme.md42
-rw-r--r--keyboards/karn/rules.mk1
11 files changed, 362 insertions, 0 deletions
diff --git a/keyboards/karn/config.h b/keyboards/karn/config.h
new file mode 100644
index 0000000000..2e737bfd71
--- /dev/null
+++ b/keyboards/karn/config.h
@@ -0,0 +1,18 @@
+// Copyright 2023 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#define DIRECT_PINS {{NO_PIN, A15,A8, B15, B14, B13}, \
+ {B10, B1, B0, A7, A6, A5 }, \
+ {NO_PIN, B3, B4, B5, B8, B9 }, \
+ {A4, A3, A2, NO_PIN, NO_PIN, NO_PIN}}
+
+#define DIRECT_PINS_RIGHT {{B13, B14, B15, A8, A15, NO_PIN}, \
+ {A5, A6, A7, B0, B1, B10}, \
+ {B9, B8, B5, B4, B3, NO_PIN}, \
+ {A2, A3, A4, NO_PIN, NO_PIN, NO_PIN}}
+
+#define SERIAL_USART_FULL_DUPLEX // Enable full duplex operation mode.
+#define SERIAL_USART_TX_PIN B6 // USART TX pin
+#define SERIAL_USART_RX_PIN B7 // USART RX pin
diff --git a/keyboards/karn/halconf.h b/keyboards/karn/halconf.h
new file mode 100644
index 0000000000..150de899ab
--- /dev/null
+++ b/keyboards/karn/halconf.h
@@ -0,0 +1,8 @@
+// Copyright 2023 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#define HAL_USE_SERIAL TRUE
+
+#include_next <halconf.h>
diff --git a/keyboards/karn/info.json b/keyboards/karn/info.json
new file mode 100644
index 0000000000..961aa8efd2
--- /dev/null
+++ b/keyboards/karn/info.json
@@ -0,0 +1,75 @@
+{
+ "manufacturer": "Robert Mills",
+ "keyboard_name": "karn",
+ "maintainer": "robcmills",
+ "features": {
+ "bootmagic": true,
+ "command": false,
+ "console": false,
+ "extrakey": true,
+ "mousekey": true,
+ "nkro": true
+ },
+ "development_board": "blackpill_f401",
+ "url": "https://github.com/robcmills/karn-keyboard",
+ "usb": {
+ "device_version": "1.0.0",
+ "pid": "0x0000",
+ "vid": "0xFEED"
+ },
+ "bootmagic": {
+ "matrix": [0, 1]
+ },
+ "split": {
+ "enabled": true
+ },
+ "community_layouts": ["split_3x6_3"],
+ "layouts": {
+ "LAYOUT_split_3x6_3": {
+ "layout": [
+ { "matrix": [0, 0], "x": 0, "y": 0 },
+ { "matrix": [0, 1], "x": 1, "y": 0 },
+ { "matrix": [0, 2], "x": 2, "y": 0 },
+ { "matrix": [0, 3], "x": 3, "y": 0 },
+ { "matrix": [0, 4], "x": 4, "y": 0 },
+ { "matrix": [0, 5], "x": 5, "y": 0},
+ { "matrix": [4, 0], "x": 8, "y": 0},
+ { "matrix": [4, 1], "x": 9, "y": 0 },
+ { "matrix": [4, 2], "x": 10, "y": 0 },
+ { "matrix": [4, 3], "x": 11, "y": 0 },
+ { "matrix": [4, 4], "x": 12, "y": 0},
+ { "matrix": [4, 5], "x": 13, "y": 0},
+ { "matrix": [1, 0], "x": 0, "y": 1},
+ { "matrix": [1, 1], "x": 1, "y": 1},
+ { "matrix": [1, 2], "x": 2, "y": 1 },
+ { "matrix": [1, 3], "x": 3, "y": 1 },
+ { "matrix": [1, 4], "x": 4, "y": 1 },
+ { "matrix": [1, 5], "x": 5, "y": 1},
+ { "matrix": [5, 0], "x": 8, "y": 1},
+ { "matrix": [5, 1], "x": 9, "y": 1 },
+ { "matrix": [5, 2], "x": 10, "y": 1 },
+ { "matrix": [5, 3], "x": 11, "y": 1 },
+ { "matrix": [5, 4], "x": 12, "y": 1},
+ { "matrix": [5, 5], "x": 13, "y": 1},
+ { "matrix": [2, 0], "x": 0, "y": 2},
+ { "matrix": [2, 1], "x": 1, "y": 2},
+ { "matrix": [2, 2], "x": 2, "y": 2 },
+ { "matrix": [2, 3], "x": 3, "y": 2 },
+ { "matrix": [2, 4], "x": 4, "y": 2 },
+ { "matrix": [2, 5], "x": 5, "y": 2},
+ { "matrix": [6, 0], "x": 8, "y": 2},
+ { "matrix": [6, 1], "x": 9, "y": 2 },
+ { "matrix": [6, 2], "x": 10, "y": 2 },
+ { "matrix": [6, 3], "x": 11, "y": 2 },
+ { "matrix": [6, 4], "x": 12, "y": 2},
+ { "matrix": [6, 5], "x": 13, "y": 2},
+ { "matrix": [3, 0], "x": 3.5, "y": 3.25 },
+ { "matrix": [3, 1], "x": 4.5, "y": 3.5 },
+ { "matrix": [3, 2], "x": 5.5, "y": 3.75 },
+ { "matrix": [7, 0], "x": 7.5, "y": 3.75 },
+ { "matrix": [7, 1], "x": 8.5, "y": 3.5 },
+ { "matrix": [7, 2], "x": 9.5, "y": 3.25 }
+ ]
+ }
+ }
+}
diff --git a/keyboards/karn/keymaps/colemak/config.h b/keyboards/karn/keymaps/colemak/config.h
new file mode 100644
index 0000000000..71eb08ed1e
--- /dev/null
+++ b/keyboards/karn/keymaps/colemak/config.h
@@ -0,0 +1,13 @@
+// Copyright 2023 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+// Equivalent to zmk behavior-hold-tap tap-preferred flavor
+// Do not force the mod-tap key press to be handled as a modifier
+// if any other key was pressed while the mod-tap key is held down.
+#define IGNORE_MOD_TAP_INTERRUPT_PER_KEY
+
+// Equivalent to zmk behavior-hold-tap hold-preferred flavor
+#define HOLD_ON_OTHER_KEY_PRESS_PER_KEY
+
diff --git a/keyboards/karn/keymaps/colemak/keymap.c b/keyboards/karn/keymaps/colemak/keymap.c
new file mode 100644
index 0000000000..dbe78c0dad
--- /dev/null
+++ b/keyboards/karn/keymaps/colemak/keymap.c
@@ -0,0 +1,96 @@
+// Copyright 2023 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0
+
+#include QMK_KEYBOARD_H
+
+// Tap Dance declarations
+enum {
+ TD_F1_F11,
+ TD_F2_F12,
+};
+
+// Tap Dance definitions
+qk_tap_dance_action_t tap_dance_actions[] = {
+ // Tap once for F1, twice for F11
+ [TD_F1_F11] = ACTION_TAP_DANCE_DOUBLE(KC_F1, KC_F11),
+ [TD_F2_F12] = ACTION_TAP_DANCE_DOUBLE(KC_F2, KC_F12),
+};
+
+bool get_hold_on_other_key_press(uint16_t keycode, keyrecord_t *record) {
+ switch (keycode) {
+ case SFT_T(KC_Z): // Special case for Shift
+ return true; // Immediately select the hold action when another key is pressed.
+ case SFT_T(KC_ESC):
+ return true;
+ default:
+ return false; // Do not select the hold action when another key is pressed.
+ }
+}
+
+bool get_ignore_mod_tap_interrupt(uint16_t keycode, keyrecord_t *record) {
+ switch (keycode) {
+ case CTL_T(KC_X):
+ return true;
+ case ALT_T(KC_C):
+ return true;
+ case CMD_T(KC_V):
+ return true;
+ case CMD_T(KC_M):
+ return true;
+ case ALT_T(KC_COMM):
+ return true;
+ case CTL_T(KC_DOT):
+ return true;
+ case KC_X:
+ return true;
+ case KC_C:
+ return true;
+ case KC_V:
+ return true;
+ case KC_M:
+ return true;
+ case KC_COMM:
+ return true;
+ case KC_DOT:
+ return true;
+ default:
+ return false;
+ }
+}
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+
+ // default (colemak)
+ [0] = LAYOUT_split_3x6_3(
+ KC_NO, KC_Q, KC_W, KC_F, KC_P, KC_G, KC_J, KC_L, KC_U, KC_Y, KC_SCLN, KC_NO,
+ HYPR_T(KC_TAB),KC_A, KC_R, KC_S, KC_T, KC_D, KC_H, KC_N, KC_E, KC_I, KC_O, HYPR_T(KC_ENT),
+ KC_NO, SFT_T(KC_Z),CTL_T(KC_X),ALT_T(KC_C),CMD_T(KC_V),KC_B, KC_K, CMD_T(KC_M),ALT_T(KC_COMM),CTL_T(KC_DOT),RSFT_T(KC_SLSH),KC_NO,
+ MO(1), SFT_T(KC_ESC),MO(3), KC_BSPC,KC_SPC,MO(2)
+ ),
+
+ // symbols
+ [1] = LAYOUT_split_3x6_3(
+ _______, KC_BSLS, KC_GRV, KC_QUOT, KC_DQT, KC_LCBR, KC_RCBR, KC_MINS, KC_EQL, KC_LBRC, KC_RBRC, _______,
+ _______, KC_EXLM, KC_AT, KC_HASH, KC_DLR, KC_PERC, KC_CIRC, KC_AMPR, KC_ASTR, KC_LPRN, KC_RPRN, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, KC_DEL, _______, _______
+ ),
+
+ // nav
+ [2] = LAYOUT_split_3x6_3(
+ _______, _______, KC_Q, _______, _______, KC_VOLU, _______, _______, _______, KC_SCLN, _______, _______,
+ _______, C(KC_UP),C(KC_DOWN),G(KC_GRV), G(KC_TAB), KC_VOLD, KC_LEFT, KC_DOWN, KC_UP, KC_RGHT, KC_CAPS, _______,
+ _______, _______, _______, _______, _______, KC_MUTE, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, _______, _______, _______
+ ),
+
+ // numbers
+ [3] = LAYOUT_split_3x6_3(
+ _______, TD(TD_F1_F11), TD(TD_F2_F12), KC_F3, KC_F4, KC_F5, KC_F6, KC_F7, KC_F8, KC_F9, KC_F10, _______,
+ _______, KC_1, KC_2, KC_3, KC_4, KC_5, KC_6, KC_7, KC_8, KC_9, KC_0, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, _______, _______, _______
+ )
+};
+
diff --git a/keyboards/karn/keymaps/colemak/readme.md b/keyboards/karn/keymaps/colemak/readme.md
new file mode 100644
index 0000000000..8d3be932fe
--- /dev/null
+++ b/keyboards/karn/keymaps/colemak/readme.md
@@ -0,0 +1,58 @@
+```
+ /*
+ * ┌─────┬─────┬─────┬─────┬─────┐ ┌─────┬─────┬─────┬─────┬─────┐
+ * │ Q │ W │ F │ P │ G │ BASE │ J │ L │ U │ Y │ ; │
+ * │ │ │ │ │ │ LAYER │ │ │ │ │ │
+ * ┌─────┼─────┼─────┼─────┼─────┼─────┤ ┌─────┐ ├─────┼─────┼─────┼─────┼─────┼─────┐
+ * │ TAB │ A │ R │ S │ T │ D │ │ TAP │ │ H │ N │ E │ I │ O │ ENT │
+ * │ HYP │ │ │ │ │ │ │ HOLD│ │ │ │ │ │ │ HYP │
+ * └─────┼─────┼─────┼─────┼─────┼─────┤ └─────┘ ├─────┼─────┼─────┼─────┼─────┼─────┘
+ * │ Z │ X │ C │ V │ B │ │ K │ M │ , │ . │ / │
+ * │ SFT │ CTL │ ALT │ CMD │ │ │ │ CMD │ ALT │ CTL │ SFT │
+ * └─────┴─────┴─────┼─────┼─────┼─────┐ ┌─────┼─────┼─────┼─────┴─────┴─────┘
+ * │ │ ESC │ │ │ BAK │ SPC │ │
+ * │ SYM │ SFT │ NUM │ │ │ │ NAV │
+ * └─────┴─────┴─────┘ └─────┴─────┴─────┘
+ * ┌─────┬─────┬─────┬─────┬─────┐ ┌─────┬─────┬─────┬─────┬─────┐
+ * │ \ │ ` │ ' │ " │ { │ SYM │ } │ - │ = │ [ │ ] │
+ * │ │ │ │ │ │ LAYER │ │ │ │ │ │
+ * ┌─────┼─────┼─────┼─────┼─────┼─────┤ ├─────┼─────┼─────┼─────┼─────┼─────┐
+ * │ │ ! │ @ │ # │ $ │ % │ │ ^ │ & │ * │ ( │ ) │ │
+ * │ │ │ │ │ │ │ │ │ │ │ │ │ │
+ * └─────┼─────┼─────┼─────┼─────┼─────┤ ├─────┼─────┼─────┼─────┼─────┼─────┘
+ * │ │ │ │ │ │ │ │ │ │ │ │
+ * │ │ │ │ │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┼─────┼─────┼─────┐ ┌─────┼─────┼─────┼─────┴─────┴─────┘
+ * │ │ │ │ │ DEL │ │ │
+ * │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┘ └─────┴─────┴─────┘
+ * ┌─────┬─────┬─────┬─────┬─────┐ ┌─────┬─────┬─────┬─────┬─────┐
+ * │ │ │ │ │ VOL │ NAV │ │ │ │ │ │
+ * │ │ │ │ │ UP │ LAYER │ │ │ │ │ │
+ * ┌─────┼─────┼─────┼─────┼─────┼─────┤ ├─────┼─────┼─────┼─────┼─────┼─────┐
+ * │ │ CTL │ CTL │ CMD │ CMD │ VOL │ │ ← │ ↓ │ ↑ │ → │CAPS │ │
+ * │ │ + ↓ │ + ↑ │ + ` │ +TAB│ DOWN│ │ │ │ │ │LOCK │ │
+ * └─────┼─────┼─────┼─────┼─────┼─────┤ ├─────┼─────┼─────┼─────┼─────┼─────┘
+ * │ │ │ │ │ MUTE│ │ │ │ │ │ │
+ * │ │ │ │ │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┼─────┼─────┼─────┐ ┌─────┼─────┼─────┼─────┴─────┴─────┘
+ * │ │ │ │ │ │ │ │
+ * │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┘ └─────┴─────┴─────┘
+ * ┌─────┬─────┬─────┬─────┬─────┐ ┌─────┬─────┬─────┬─────┬─────┐
+ * │ F1 │ F2 │ F3 │ F4 │ F5 │ NUM │ F6 │ F7 │ F8 │ F9 │ F10 │
+ * │ F11 │ F12 │ │ │ │ LAYER │ │ │ │ │ │
+ * ┌─────┼─────┼─────┼─────┼─────┼─────┤ ┌─────┐ ├─────┼─────┼─────┼─────┼─────┼─────┐
+ * │ │ 1 │ 2 │ 3 │ 4 │ 5 │ │ TAP │ │ 6 │ 7 │ 8 │ 9 │ 0 │ │
+ * │ │ │ │ │ │ │ │TAPx2│ │ │ │ │ │ │ │
+ * └─────┼─────┼─────┼─────┼─────┼─────┤ └─────┘ ├─────┼─────┼─────┼─────┼─────┼─────┘
+ * │ │ │ │ │ │ │ │ │ │ │ │
+ * │ │ │ │ │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┼─────┼─────┼─────┐ ┌─────┼─────┼─────┼─────┴─────┴─────┘
+ * │ │ │ │ │ │ │ │
+ * │ │ │ │ │ │ │ │
+ * └─────┴─────┴─────┘ └─────┴─────┴─────┘
+ */
+```
+
+
diff --git a/keyboards/karn/keymaps/colemak/rules.mk b/keyboards/karn/keymaps/colemak/rules.mk
new file mode 100644
index 0000000000..e5ddcae8d9
--- /dev/null
+++ b/keyboards/karn/keymaps/colemak/rules.mk
@@ -0,0 +1 @@
+TAP_DANCE_ENABLE = yes
diff --git a/keyboards/karn/keymaps/default/keymap.c b/keyboards/karn/keymaps/default/keymap.c
new file mode 100644
index 0000000000..5f679552d9
--- /dev/null
+++ b/keyboards/karn/keymaps/default/keymap.c
@@ -0,0 +1,41 @@
+// Copyright 2023 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0
+
+#include QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+
+ // default (qwerty)
+ [0] = LAYOUT_split_3x6_3(
+ KC_NO, KC_Q, KC_W, KC_E, KC_R, KC_T, KC_Y, KC_U, KC_I, KC_O, KC_P, KC_NO,
+ HYPR_T(KC_TAB),KC_A, KC_S, KC_D, KC_F, KC_G, KC_H, KC_J, KC_K, KC_L, KC_SCLN, HYPR_T(KC_ENT),
+ KC_NO, SFT_T(KC_Z),CTL_T(KC_X),ALT_T(KC_C),CMD_T(KC_V),KC_B, KC_N, CMD_T(KC_M),ALT_T(KC_COMM),CTL_T(KC_DOT),RSFT_T(KC_SLSH),KC_NO,
+ MO(1), SFT_T(KC_ESC),MO(3), KC_BSPC,KC_SPC,MO(2)
+ ),
+
+ // symbols
+ [1] = LAYOUT_split_3x6_3(
+ _______, KC_BSLS, KC_GRV, KC_QUOT, KC_DQT, KC_LCBR, KC_RCBR, KC_MINS, KC_EQL, KC_LBRC, KC_RBRC, _______,
+ _______, KC_EXLM, KC_AT, KC_HASH, KC_DLR, KC_PERC, KC_CIRC, KC_AMPR, KC_ASTR, KC_LPRN, KC_RPRN, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, KC_DEL, _______, _______
+ ),
+
+ // nav
+ [2] = LAYOUT_split_3x6_3(
+ _______, _______, _______, _______, _______, KC_VOLU, _______, _______, _______, _______, _______, _______,
+ _______, C(KC_UP),C(KC_DOWN),G(KC_GRV), G(KC_TAB), KC_VOLD, KC_LEFT, KC_DOWN, KC_UP, KC_RGHT, KC_CAPS, _______,
+ _______, _______, _______, _______, _______, KC_MUTE, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, _______, _______, _______
+ ),
+
+ // numbers
+ [3] = LAYOUT_split_3x6_3(
+ _______, KC_F1, KC_F2, KC_F3, KC_F4, KC_F5, KC_F6, KC_F7, KC_F8, KC_F9, KC_F10, _______,
+ _______, KC_1, KC_2, KC_3, KC_4, KC_5, KC_6, KC_7, KC_8, KC_9, KC_0, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, _______, _______, _______
+ )
+};
+
diff --git a/keyboards/karn/mcuconf.h b/keyboards/karn/mcuconf.h
new file mode 100644
index 0000000000..766fa7d06e
--- /dev/null
+++ b/keyboards/karn/mcuconf.h
@@ -0,0 +1,9 @@
+// Copyright 2022 Robert Mills (@robcmills)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include_next <mcuconf.h>
+
+#undef STM32_SERIAL_USE_USART1
+#define STM32_SERIAL_USE_USART1 TRUE
diff --git a/keyboards/karn/readme.md b/keyboards/karn/readme.md
new file mode 100644
index 0000000000..037cc5d652
--- /dev/null
+++ b/keyboards/karn/readme.md
@@ -0,0 +1,42 @@
+# Karn 2
+
+Split, ortholinear, non-staggered, diodeless, 38 key keyboard, with a unique set of 1.5u thumb arc keys and 1.5u pinky reach keys.
+
+* Keyboard Maintainer: [Robert Mills](https://github.com/robcmills)
+* Hardware Supported: Blackpill STM32F401
+
+Based on the excellent [cantor](https://github.com/diepala/cantor), and inspired by the popular [corne](https://github.com/foostan/crkbd), [ferris](https://github.com/pierrechevalier83/ferris) and [sweep](https://github.com/davidphilipbarr/Sweep) keyboards.
+
+[https://github.com/robcmills/karn-keyboard](https://github.com/robcmills/karn-keyboard)
+
+![karn-2-left](https://i.imgur.com/vm6XFyIh.jpeg)
+
+![karn-2-full](https://i.imgur.com/R7WnlC3h.jpeg)
+
+![karn-2-pcb](https://i.imgur.com/EQqyyEDh.png)
+
+
+### Make
+
+Make example for this keyboard (after setting up your build environment):
+
+ make karn:default
+
+Flashing example for this keyboard:
+
+ make karn:default:flash
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
+
+
+### Bootloader
+
+Enter the bootloader in 3 ways:
+
+* **Bootmagic reset**: Hold down the top left key and plug in the keyboard. For the right side, hold the top right key and plug the keyboard.
+* **Physical reset button**:
+ * Press and hold the BOOT0 button.
+ * Press and release the NRST button.
+ * Release the BOOT0 button.
+* **Keycode in layout**: Press the key mapped to `QK_BOOT` if it is available
+
diff --git a/keyboards/karn/rules.mk b/keyboards/karn/rules.mk
new file mode 100644
index 0000000000..c6e2988321
--- /dev/null
+++ b/keyboards/karn/rules.mk
@@ -0,0 +1 @@
+SERIAL_DRIVER = usart