Parity Checker

When enabled, the parity checker calculates the parity of the data bits in incoming frames and compares the result with the parity bit of the corresponding frame. If a parity error is detected, the Parity Error flag (PERR in USART.RXDATAH) is set.

If USART LIN mode is enabled (by writing RXMODE to '1' in USART.CTRLB), a parity check is only performed on the protected identifier field. An parity error is detected if one of the equations below is not true which sets PERR in USART.RXDATAH.

Figure 1. Protected identifier field and mapping of identifier and parity bits