LED_REG
#define CLEAR_LEDS() *LED_REG = *LED_REG | 0x1e0
#define LED_ON(led) *LED_REG = *LED_REG & ( ~(1<<(led+4)) & 0x1E0 )
#define LED_OFF(led) *LED_REG = *LED_REG | ( ~(1<<(led+4)) & 0x1E0 )