+#define WAIT_US (1000000L/SERIAL_SOFT_BAUD)
+
+#ifdef SERIAL_SOFT_LOGIC_NEGATIVE
+ #define SERIAL_SOFT_RXD_IN() !(SERIAL_SOFT_RXD_READ())
+ #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_LO()
+ #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_HI()
+#else
+ #define SERIAL_SOFT_RXD_IN() !!(SERIAL_SOFT_RXD_READ())
+ #define SERIAL_SOFT_TXD_ON() SERIAL_SOFT_TXD_HI()
+ #define SERIAL_SOFT_TXD_OFF() SERIAL_SOFT_TXD_LO()
+#endif
+
+#ifdef SERIAL_SOFT_PARITY_EVEN
+ #define SERIAL_SOFT_PARITY_VAL 0
+#elif defined(SERIAL_SOFT_PARITY_ODD)
+ #define SERIAL_SOFT_PARITY_VAL 1
+#endif
+
+/* debug for signal timing, see debug pin with oscilloscope */
+#define SERIAL_SOFT_DEBUG
+#ifdef SERIAL_SOFT_DEBUG
+ #define SERIAL_SOFT_DEBUG_INIT() (DDRD |= 1<<7)
+ #define SERIAL_SOFT_DEBUG_TGL() (PORTD ^= 1<<7)
+#else
+ #define SERIAL_SOFT_DEBUG_INIT()
+ #define SERIAL_SOFT_DEBUG_TGL()
+#endif
+