#ifdef PS2_USE_USART
#if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)
/* XCK for clock line and RXD for data line */
#ifdef PS2_USE_USART
#if defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)
/* XCK for clock line and RXD for data line */