TWI_IRQEN_DNACK
#define TWI_IRQ_DNACK (TWI_IRQEN_DNACK << 8)
#define TWI_IRQEN (TWI_IRQEN_COMPL | TWI_IRQEN_ANACK | TWI_IRQEN_DNACK)
if ((reg & TWI_IRQEN_DNACK) != 0 && (reg & TWI_IRQ_DNACK)) {