[keyboard] Add chavdai40 keyboard (#9820)

* On branch add_chavdai40_keyboard

Changes to be committed:
	new file:   keyboards/chavdai40/boards/GENERIC_STM32_F042X6/board.c
	new file:   keyboards/chavdai40/boards/GENERIC_STM32_F042X6/board.h
	new file:   keyboards/chavdai40/boards/GENERIC_STM32_F042X6/board.mk
	new file:   keyboards/chavdai40/bootloader_defs.h
	new file:   keyboards/chavdai40/chavdai40.c
	new file:   keyboards/chavdai40/chavdai40.h
	new file:   keyboards/chavdai40/chconf.h
	new file:   keyboards/chavdai40/config.h
	new file:   keyboards/chavdai40/halconf.h
	new file:   keyboards/chavdai40/info.json
	new file:   keyboards/chavdai40/keymaps/42keys-dvorak/config.h
	new file:   keyboards/chavdai40/keymaps/42keys-dvorak/keymap.c
	new file:   keyboards/chavdai40/keymaps/42keys-eucalyn/config.h
	new file:   keyboards/chavdai40/keymaps/42keys-eucalyn/keymap.c
	new file:   keyboards/chavdai40/keymaps/42keys-qwerty/config.h
	new file:   keyboards/chavdai40/keymaps/42keys-qwerty/keymap.c
	new file:   keyboards/chavdai40/keymaps/44keys-dvorak/config.h
	new file:   keyboards/chavdai40/keymaps/44keys-dvorak/keymap.c
	new file:   keyboards/chavdai40/keymaps/44keys-eucalyn/config.h
	new file:   keyboards/chavdai40/keymaps/44keys-eucalyn/keymap.c
	new file:   keyboards/chavdai40/keymaps/44keys-qwerty/config.h
	new file:   keyboards/chavdai40/keymaps/44keys-qwerty/keymap.c
	new file:   keyboards/chavdai40/keymaps/default/config.h
	new file:   keyboards/chavdai40/keymaps/default/keymap.c
	new file:   keyboards/chavdai40/mcuconf.h
	new file:   keyboards/chavdai40/readme.md
	new file:   keyboards/chavdai40/rules.mk

* commit suggestions of zvecr and fauxpark, thanks

* commit suggestions of fauxpark, thanks

* commit suggestions of fauxpark, thanks

* commit suggestions of drashna, thanks

1 files changed, 74 insertions, 0 deletions

diff --git a/keyboards/chavdai40/config.h b/keyboards/chavdai40/config.h
new file mode 100644
index 000000000..a3dcf84e9
--- /dev/null
+++ b/keyboards/chavdai40/config.h
@@ -0,0 +1,74 @@
+/* Copyright 2020 t-miyajima
+ *
+ * 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/>.
+ */
+
+
+#pragma once
+
+#include "config_common.h"
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID       0x16D0
+#define PRODUCT_ID      0x0F95
+#define DEVICE_VER      0x0001
+#define MANUFACTURER    t-miyajima
+#define PRODUCT         Chavdai40
+
+/* usb power settings */
+#define USB_MAX_POWER_CONSUMPTION 100
+
+/* key matrix size */
+#define MATRIX_ROWS 4
+#define MATRIX_COLS 13
+
+ 
+#define MATRIX_ROW_PINS { A0, A15, B5, B6 }
+#define MATRIX_COL_PINS { B8, B4, B3, B2, B1, B0, A7, A6, A5, A4, A3, A2, A1 }
+#define UNUSED_PINS
+
+/* COL2ROW, ROW2COL*/
+#define DIODE_DIRECTION COL2ROW
+
+/* Debounce reduces chatter (unintended double-presses) - set 0 if debouncing is not needed */
+#define DEBOUNCE 5
+
+/* define if matrix has ghost (lacks anti-ghosting diodes) */
+//#define MATRIX_HAS_GHOST
+
+/* If defined, GRAVE_ESC will always act as ESC when CTRL is held.
+ * This is userful for the Windows task manager shortcut (ctrl+shift+esc).
+ */
+// #define GRAVE_ESC_CTRL_OVERRIDE
+
+/*
+ * Force NKRO
+ *
+ * Force NKRO (nKey Rollover) to be enabled by default, regardless of the saved
+ * state in the bootmagic EEPROM settings. (Note that NKRO must be enabled in the
+ * makefile for this to work.)
+ *
+ * If forced on, NKRO can be disabled via magic key (default = LShift+RShift+N)
+ * until the next keyboard reset.
+ *
+ * NKRO may prevent your keystrokes from being detected in the BIOS, but it is
+ * fully operational during normal computer usage.
+ *
+ * For a less heavy-handed approach, enable NKRO via magic key (LShift+RShift+N)
+ * or via bootmagic (hold SPACE+N while plugging in the keyboard). Once set by
+ * bootmagic, NKRO mode will always be enabled until it is toggled again during a
+ * power-up.
+ *
+ */
+//#define FORCE_NKRO