Keyboard: Add new keyboard Zinc (#4245)

* Add Zinc keyboard

* Fix photo

* Fix readme.md

* Fix RGB LED init of monks/keymap.c

* Fix default keymap and readme.jp

* Fix change DEFS of RGB ANIMATIONS to LED_ANIMATIONS

* Add EOL

* Use serial_config_simpleapi.h

* Fix comment char

* Fix error handling in split_scomm.c : mtei works

* Fix keymaps

* Remove DISABLE_LEADER definition

* Remove pro_micro.h

* Add 2 spaces after Hardware name

* Fix keymaps
  - remove audio codes
  - change LAYOUT to LAYOUT_ortho_4X12
  - change "persistent_default_layer_set" to core function

* Use the Community Layouts feature
  -  with some clean up

1 files changed, 49 insertions, 0 deletions

diff --git a/keyboards/zinc/i2c.h b/keyboards/zinc/i2c.h
new file mode 100644
index 0000000000..47cf6bd1b2
--- /dev/null
+++ b/keyboards/zinc/i2c.h
@@ -0,0 +1,49 @@
+#ifndef I2C_H
+#define I2C_H
+
+#include <stdint.h>
+
+#ifndef F_CPU
+#define F_CPU 16000000UL
+#endif
+
+#define I2C_READ 1
+#define I2C_WRITE 0
+
+#define I2C_ACK 1
+#define I2C_NACK 0
+
+#define SLAVE_BUFFER_SIZE 0x10
+
+// i2c SCL clock frequency 400kHz
+#define SCL_CLOCK  400000L
+
+extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
+
+void i2c_master_init(void);
+uint8_t i2c_master_start(uint8_t address);
+void i2c_master_stop(void);
+uint8_t i2c_master_write(uint8_t data);
+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