SAM4L Datasheet, PDF (627/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
• TXEMPTY: Transmitter Empty
0: The transmitter is either disabled or there are characters in THR, or in the transmit shift register.
1: There are no characters in neither THR, nor in the transmit shift register.
This bit is cleared by writing a one to CR.STTBRK.
• TIMEOUT: Receiver Time-out
0: There has not been a time-out since the last Start Time-out command (CR.STTTO), or RTOR.TO is zero.
1: There has been a time-out since the last Start Time-out command.
This bit is cleared by writing a one to CR.STTTO or CR.RETTO.
• PARE: Parity Error
0: Either no parity error has been detected, or the parity bit is a zero in multidrop mode, since the last RSTSTA.
1: Either at least one parity error has been detected, or the parity bit is a one in multidrop mode, since the last RSTSTA.
This bit is cleared by writing a one to CR.RSTSTA.
• FRAME: Framing Error
0: No stop bit has been found as low since the last RSTSTA.
1: At least one stop bit has been found as low since the last RSTSTA.
This bit is cleared by writing a one to CR.RSTSTA.
• OVRE: Overrun Error
0: No overrun error has occurred since the last RSTSTA.
1: At least one overrun error has occurred since the last RSTSTA.
This bit is cleared by writing a one to CR.RSTSTA.
• RXBRK: Break Received/End of Break
0: No Break received or End of Break detected since the last RSTSTA.
1: Break received or End of Break detected since the last RSTSTA.
This bit is cleared by writing a one to CR.RSTSTA.
• TXRDY: Transmitter Ready
0: The transmitter is either disabled, or a character in THR is waiting to be transferred to the transmit shift register, or an
STTBRK command has been requested. As soon as the transmitter is enabled, TXRDY is set.
1: There is no character in the THR.
This bit is cleared by writing a one to CR.STTBRK.
• RXRDY: Receiver Ready
0: The receiver is either disabled, or no complete character has been received since the last read of RHR. If characters were
being received when the receiver was disabled, RXRDY is set when the receiver is enabled.
1: At least one complete character has been received and RHR has not yet been read.
This bit is cleared when the Receive Holding Register (RHR) is read.
42023C–SAM–02/2013
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