ATMEGA8515L-8AU Atmel, ATMEGA8515L-8AU Datasheet - Page 136

• Manufacturer Part Number: ATMEGA8515L-8AU
• Description: IC AVR MCU 8K 8MHZ 3V 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8515L-8AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: EBI/EMI, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 35
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Processor Series: ATMEGA8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: SPI, USART
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 35
• Number Of Timers: 2
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Minimum Operating Temperature: - 40 C
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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ATmega8515(L)
Figure 64. USART Block Diagram
Note:
The dashed boxes in the block diagram separate the three main parts of the USART
(listed from the top): Clock Generator, Transmitter and Receiver. Control Registers are
shared by all units. The clock generation logic consists of synchronization logic for exter-
nal clock input used by synchronous slave operation, and the baud rate generator. The
XCK (Transfer Clock) pin is only used by Synchronous Transfer mode. The Transmitter
consists of a single write buffer, a serial Shift Register, parity generator and control logic
for handling different serial frame formats. The write buffer allows a continuous transfer
of data without any delay between frames. The Receiver is the most complex part of the
USART module due to its clock and data recovery units. The recovery units are used for
asynchronous data reception. In addition to the recovery units, the Receiver includes a
Parity Checker, control logic, a Shift Register and a two level receive buffer (UDR). The
Receiver supports the same frame formats as the Transmitter, and can detect Frame
Error, Data OverRun and Parity Errors.
1. Refer to Figure 1 on page 2, Table 37 on page 73, and Table 31 on page 69 for
USART pin placement.
UCSRA
TRANSMIT SHIFT REGISTER
RECEIVE SHIFT REGISTER
BAUD RATE GENERATOR
UDR (Transmit)
UDR (Receive)
UBRR[H:L]
(1)
UCSRB
GENERATOR
SYNC LOGIC
RECOVERY
RECOVERY
CHECKER
PARITY
PARITY
CLOCK
DATA
OSC
Clock Generator
CONTROL
CONTROL
CONTROL
CONTROL
CONTROL
Transmitter
PIN
PIN
PIN
RX
TX
Receiver
UCSRC
2512K–AVR–01/10
XCK
RxD
TxD