ATMEGA169L-8MI Atmel, ATMEGA169L-8MI Datasheet - Page 173

• Manufacturer Part Number: ATMEGA169L-8MI
• Description: IC MCU AVR 16K LV 8MHZ IND 64QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA169L-8MI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-MLF®, 64-QFN
• For Use With: ATAVRISP2 - PROGRAMMER AVR IN SYSTEMATAVRBFLY - KIT EVALUATION AVR BUTTERFLYATSTK502 - MOD EXPANSION AVR STARTER 500
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: ATMEGA169L-4MI; ATMEGA169L-4MI

USART Baud Rate Registers –
UBRRL and UBRRH
2514H–AVR–05/03
• Bit 2:1 – UCSZ1:0: Character Size
The UCSZ1:0 bits combined with the UCSZ2 bit in UCSRB sets the number of data bits
(Character SiZe) in a frame the Receiver and Transmitter use.
Table 77. UCSZ Bits Settings
• Bit 0 – UCPOL: Clock Polarity
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 78. UCPOL Bit Settings
• Bit 15:12 – 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
UCSZ2
0
0
0
0
1
1
1
1
Transmitted Data Changed (Output of
TxD Pin)
Rising XCK Edge
Falling XCK Edge
R/W
15
R
–
7
0
0
R/W
14
UCSZ1
R
–
6
0
0
0
0
1
1
0
0
1
1
R/W
13
–
5
R
0
0
R/W
12
R
–
4
0
0
UBRR[7:0]
UCSZ0
0
1
0
1
0
1
0
1
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
Character Size
5-bit
6-bit
7-bit
8-bit
Reserved
Reserved
Reserved
9-bit
10
2
0
0
UBRR[11:8]
ATmega169V/L
R/W
R/W
9
1
0
0
R/W
R/W
8
0
0
0
UBRRH
UBRRL
173