A_DUART
#define A_DUART_CHANREG(chan,reg) (A_DUART + DUART_CHANREG_SPACING*(chan) + (reg))
#define A_DUART_IMRREG(chan) (A_DUART + R_DUART_IMRREG(chan))
#define A_DUART_ISRREG(chan) (A_DUART + R_DUART_ISRREG(chan))