AT91M55800A_0212 Datasheet, PDF (142/227 Pages) ATMEL Corporation – AT91 ARM Thumb Microcontrollers

USART Channel Status Register
Name:
US_CSR
Access Type:
Read-only
Reset:
0x18
Offset:
0x14
31
30
29
–
–
–
23
22
21
–
–
–
15
14
13
–
–
–
7
PARE
6
FRAME
5
OVRE
28
–
20
–
12
–
4
ENDTX
27
–
19
–
11
–
3
ENDRX
26
–
18
–
10
–
2
RXBRK
25
–
17
–
9
TXEMPTY
1
TXRDY
24
–
16
–
8
TIMEOUT
0
RXRDY
• RXRDY: Receiver Ready (Code Label US_RXRDY)
0 = No complete character has been received since the last read of the US_RHR or the receiver is disabled.
1 = At least one complete character has been received and the US_RHR has not yet been read.
• TXRDY: Transmitter Ready (Code Label US_TXRDY)
0 = US_THR contains a character waiting to be transferred to the Transmit Shift Register, or an STTBRK command has
been requested.
1 = US_THR is empty and there is no Break request pending TSR availability.
Equal to zero when the USART is disabled or at reset. Transmitter Enable command (in US_CR) sets this bit to one.
• RXBRK: Break Received/End of Break (Code Label US_RXBRK)
0 = No Break Received nor End of Break detected since the last “Reset Status Bits” command in the Control Register.
1 = Break Received or End of Break detected since the last “Reset Status Bits” command in the Control Register.
• ENDRX: End of Receive Transfer (Code Label US_ENDRX)
0 = The End of Transfer signal from the Peripheral Data Controller channel dedicated to the receiver is inactive.
1 = The End of Transfer signal from the Peripheral Data Controller channel dedicated to the receiver is active.
• ENDTX: End of Transmit Transfer (Code Label US_ENDTX)
0 = The End of Transfer signal from the Peripheral Data Controller channel dedicated to the transmitter is inactive.
1 = The End of Transfer signal from the Peripheral Data Controller channel dedicated to the transmitter is active.
• OVRE: Overrun Error (Code Label US_OVRE)
0 = No byte has been transferred from the Receive Shift Register to the US_RHR when RxRDY was asserted since the
last “Reset Status Bits” command.
1 = At least one byte has been transferred from the Receive Shift Register to the US_RHR when RxRDY was asserted
since the last “Reset Status Bits” command.
• FRAME: Framing Error (Code Label US_FRAME)
0 = No stop bit has been detected low since the last “Reset Status Bits” command.
1 = At least one stop bit has been detected low since the last “Reset Status Bits” command.
• PARE: Parity Error (Code Label US_PARE)
1 = At least one parity bit has been detected false (or a parity bit high in multi-drop mode) since the last “Reset Status
Bits” command.
0 = No parity bit has been detected false (or a parity bit high in multi-drop mode) since the last “Reset Status Bits” com-
mand.
• TIMEOUT: Receiver Time-out (Code Label US_TIMEOUT)
0 = There has not been a time-out since the last “Start Time-out” command or the Time-out Register is 0.
1 = There has been a time-out since the last “Start Time-out” command.
• TXEMPTY: Transmitter Empty (Code Label US_TXEMPTY)
0 = There are characters in either US_THR or the Transmit Shift Register or a Break is being transmitted.
1 = There are no characters in US_THR and the Transmit Shift Register and Break is not active.
Equal to zero when the USART is disabled or at reset. Transmitter Enable command (in US_CR) sets this bit to one.
142 AT91M55800A
1745C–ATARM–12/02