+#ifdef HHKB_POWER_SAVING
+static inline void KEY_POWER_ON(void) {
+ DDRB = 0xFF; PORTB = 0x40; // change pins output
+ DDRD |= (1<<4); PORTD |= (1<<4); // MOS FET switch on
+ /* Without this wait you will miss or get false key events. */
+ _delay_ms(5); // wait for powering up
+}
+static inline void KEY_POWER_OFF(void) {
+ /* input with pull-up consumes less than without it when pin is open. */
+ DDRB = 0x00; PORTB = 0xFF; // change pins input with pull-up
+ DDRD |= (1<<4); PORTD &= ~(1<<4); // MOS FET switch off
+}
+static inline bool KEY_POWER_STATE(void) { return PORTD & (1<<4); }
+#else