57.7.9.10 Drift Compensation

It may happen that while receiving a frame, the baud rate used by the sender is not exactly the one expected, due to sender clock drifting for instance. In such case, the hardware drift compensation algorithm is used to recover up to 16% clock drift (expected baud rate ±16% is supported).

Drift compensation is available only in 16X Oversampling mode. To enable the hardware system, the DRIFT bit of the FLEX_US_MAN register must be set. If the RXD edge is between one and three 16X clock cycles away from the expected edge, then the period is shortened or lengthened accordingly to center the RXD edge.

Drift compensation hardware feature allows up to 16% clock drift to be handled, provided system clock is fast enough compared to the selected baud rate.