#define ao_serial_btm_getchar ao_serial2_getchar
#define ao_serial_btm_putchar ao_serial2_putchar
#define _ao_serial_btm_pollchar _ao_serial2_pollchar
-#define _ao_serial_btm_sleep _ao_serial2_sleep
+#define _ao_serial_btm_sleep_for _ao_serial2_sleep_for
#define ao_serial_btm_set_speed ao_serial2_set_speed
#define ao_serial_btm_drain ao_serial2_drain
#define ao_serial_btm_rx_fifo (ao_stm_usart2.rx_fifo)