ATMEGA8535-16MU Atmel, ATMEGA8535-16MU Datasheet - Page 169

• Manufacturer Part Number: ATMEGA8535-16MU
• Description: IC AVR MCU 8K 16MHZ 5V 44-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8535-16MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• 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): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN Exposed Pad
• Processor Series: ATMEGA8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: 2-Wire, SPI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Package: 44MLF EP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 16 MHz
• For Use With: ATAVRISP2 - PROGRAMMER AVR IN SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

USART Baud Rate Registers –
UBRRL and UBRRH
2502K–AVR–10/06
(1)
This bit is used for Synchronous mode only. Write this bit to zero when asynchronous
mode is used. The UCPOL bit sets the relationship between data output change and
data input sample, and the synchronous clock (XCK).
Table 68. UCPOL Bit Settings
Note:
• Bit 15 – URSEL: Register Select
This bit selects between accessing the UBRRH or the UCSRC Register. It is read as
zero when reading UBRRH. The URSEL must be zero when writing the UBRRH.
• Bit 14:12 – Reserved Bits
These bits are reserved for future use. For compatibility with future devices, these bit
must be written to zero when UBRRH is written.
• Bit 11:0 – UBRR11:0: USART Baud Rate Register
This is a 12-bit register which contains the USART Baud Rate. The UBRRH contains the
four most significant bits, and the UBRRL contains the eight least significant bits of the
USART baud rate. Ongoing transmissions by the Transmitter and Receiver will be cor-
rupted if the baud rate is changed. Writing UBRRL will trigger an immediate update of
the baud rate prescaler.
Bit
Read/Write
Initial Value
UCPOL
0
1
1. The UBRRH Register shares the same I/O location as the UCSRC Register. See the
“Accessing UBRRH/UCSRC Registers” on page 163 section which describes how to
access this register.
URSEL
Transmitted Data Changed
(Output of TxD Pin)
Rising XCK Edge
Falling XCK Edge
R/W
R/W
15
7
0
0
R/W
14
R
–
6
0
0
R/W
13
R
–
5
0
0
R/W
12
R
–
4
0
0
UBRR[7:0]
R/W
R/W
11
3
0
0
Received Data Sampled
(Input on RxD Pin)
Falling XCK Edge
Rising XCK Edge
R/W
R/W
10
2
0
0
ATmega8535(L)
UBRR[11:8]
R/W
R/W
9
1
0
0
R/W
R/W
8
0
0
0
UBRRH
UBRRL
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