-/* TODO: some defines for interrupt setup */
-#define SERIAL_PIN_DDR DDRD
-#define SERIAL_PIN_PORT PORTD
-#define SERIAL_PIN_INPUT PIND
+// /////////////////////////////////////////////////////////////////
+// Need Soft Serial defines in config.h
+// /////////////////////////////////////////////////////////////////
+// ex.
+// #define SOFT_SERIAL_PIN ?? // ?? = D0,D1,D2,D3,E6
+// OPTIONAL: #define SELECT_SOFT_SERIAL_SPEED ? // ? = 1,2,3,4,5
+// // 1: about 137kbps (default)
+// // 2: about 75kbps
+// // 3: about 39kbps
+// // 4: about 26kbps
+// // 5: about 20kbps
+//
+// //// USE OLD API (compatible with let's split serial.c)
+// ex.
+// #define SERIAL_SLAVE_BUFFER_LENGTH MATRIX_ROWS/2
+// #define SERIAL_MASTER_BUFFER_LENGTH 1
+//
+// //// USE NEW API
+// //// USE simple API (using signle-type transaction function)
+// #define SERIAL_USE_SINGLE_TRANSACTION
+// //// USE flexible API (using multi-type transaction function)
+// #define SERIAL_USE_MULTI_TRANSACTION
+//
+// /////////////////////////////////////////////////////////////////