In MCXA153, the division rate for the baud rate generator register is SBR, as described in 39.6.6 Baud Rate (BAUD). Please note that there may be a difference between SBR and BRG. In MCXA153, the baud rate is calculated as baud clock ÷ ((OSR + 1) × SBR). There is no need to add 1 to SBR. For details, please refer to the User Manual (UM).