In low-frequency mode, the integer portion of the divisor is realized by the Prescaler: UCBRx = INT(N), and the fractional portion is realized by the modulator with the following nominal formula:

UCBRSx = round[( N – INT(N)) × 8] Incrementing or decrementing the UCBRSx setting by one count may give a lower maximum bit error for any given bit.

To determine if this is the case, a detailed error calculation must be performed for each bit for each UCBRSx setting.