AT32UC3L032-D3UR Atmel, AT32UC3L032-D3UR Datasheet - Page 366

• Manufacturer Part Number: AT32UC3L032-D3UR
• Description: MCU AVR32 32KB FLASH 48TLLGA
• Manufacturer: Atmel
• Series: AVR®32 UC3r

Specifications of AT32UC3L032-D3UR

• Core Processor: AVR
• Core Size: 32-Bit
• Speed: 50MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, PWM, WDT
• Number Of I /o: 36
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.62 V ~ 3.6 V
• Data Converters: A/D 9x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-TLLGA
• Processor Series: AT32UC3x
• Core: AVR32
• Data Bus Width: 32 bit
• Data Ram Size: 16 KB
• Interface Type: SPI, TWI, USART
• Maximum Clock Frequency: 50 MHz
• Number Of Programmable I/os: 36
• Number Of Timers: 7
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR32, EWAVR32-BL
• Development Tools By Supplier: AT32UC3L-EK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 9 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

19.6.3.2
32099F–11/2010
Asynchronous Receiver
in THR have been processed. When the current character processing is completed, the last
character written in THR is transferred into the Shift Register of the transmitter and THR
becomes empty, thus TXRDY rises.
Both TXRDY and TXEMPTY bits are low when the transmitter is disabled. Writing a character in
THR while TXRDY is low has no effect and the written character is lost.
Figure 19-5. Transmitter Status
If the USART is programmed in asynchronous operating mode (SYNC = 0), the receiver over-
samples the RXD input line. The oversampling is either 16 or 8 times the Baud Rate clock,
depending on the OVER bit in the Mode Register (MR).
The receiver samples the RXD line. If the line is sampled during one half of a bit time at 0, a start
bit is detected and data, parity and stop bits are successively sampled on the bit rate clock.
If the oversampling is 16, (OVER at 0), a start is detected at the eighth sample at 0. Then, data
bits, parity bit and stop bit are sampled on each 16 sampling clock cycle. If the oversampling is 8
(OVER at 1), a start bit is detected at the fourth sample at 0. Then, data bits, parity bit and stop
bit are sampled on each 8 sampling clock cycle.
The number of data bits, first bit sent and parity mode are selected by the same fields and bits
as the transmitter, i.e. respectively CHRL, MODE9, MSBF and PAR. For the synchronization
mechanism only, the number of stop bits has no effect on the receiver as it considers only one
stop bit, regardless of the field NBSTOP, so that resynchronization between the receiver and the
transmitter can occur. Moreover, as soon as the stop bit is sampled, the receiver starts looking
for a new start bit so that resynchronization can also be accomplished when the transmitter is
operating with one stop bit.
Figure 19-6
operates in asynchronous mode.
Baud Rate
TXEMPTY
TXRDY
Clock
Write
TXD
THR
and
Start
Figure 19-7
Bit
D0
D1
D2
illustrate start detection and character reception when USART
D3
D4
D5
D6
D7
Parity
Bit
Stop
Bit
Start
Bit
D0
AT32UC3L016/32/64
D1
D2
D3
D4
D5
D6
D7
Parity
Bit
Stop
Bit
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