![Atmel SAM4S Series Скачать руководство пользователя страница 713](http://html1.mh-extra.com/html/atmel/sam4s-series/sam4s-series_preliminary-data-sheet_3003408713.webp)
713
11100B–ATARM–31-Jul-12
SAM4S Series [Preliminary]
Figure 33-3. Start Bit Detection
Figure 33-4. Character Reception
33.5.2.3
Receiver Ready
When a complete character is received, it is transferred to the UART_RHR and the RXRDY sta-
tus bit in UART_SR (Status Register) is set. The bit RXRDY is automatically cleared when the
receive holding register UART_RHR is read.
Figure 33-5. Receiver Ready
33.5.2.4
Receiver Overrun
If UART_RHR has not been read by the software (or the Peripheral Data Controller or DMA
Controller) since the last transfer, the RXRDY bit is still set and a new character is received, the
OVRE status bit in UART_SR is set. OVRE is cleared when the software writes the control regis-
ter UART_CR with the bit RSTSTA (Reset Status) at 1.
Sampling Clock
URXD
True Start
Detection
D0
Baud Rate
Clock
D0
D1
D2
D3
D4
D5
D6
D7
URXD
True Start Detection
Sampling
Parity Bit
Stop Bit
Example: 8-bit, parity enabled 1 stop
1 bit
period
0.5 bit
period
D0
D1
D2
D3
D4
D5
D6
D7
P
S
S
D0
D1
D2
D3
D4
D5
D6
D7
P
URXD
Read UART_RHR
RXRDY
Содержание SAM4S Series
Страница 44: ...44 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 412: ...412 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1105: ...1105 11100B ATARM 31 Jul 12 SAM4S Series Preliminary ...
Страница 1142: ...1142 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 3 100 ball VFBGA Package Drawing ...
Страница 1143: ...1143 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 4 64 lead LQFP Package Drawing ...
Страница 1145: ...1145 11100B ATARM 31 Jul 12 SAM4S Series Preliminary Figure 43 5 64 lead QFN Package Drawing ...