ATMEGA328-AU Atmel, ATMEGA328-AU Datasheet - Page 220
ATMEGA328-AU
Manufacturer Part Number
ATMEGA328-AU
Description
IC MCU AVR 32K FLASH 32TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA328-AU
Core Processor
AVR
Core Size
8-Bit
Speed
20MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
23
Program Memory Size
32KB (16K x 16)
Program Memory Type
FLASH
Eeprom Size
1K x 8
Ram Size
2K x 8
Voltage - Supply (vcc/vdd)
1.8 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
32-TQFP, 32-VQFP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ATMEGA328-AU
Manufacturer:
SAMSUNG
Quantity:
15 000
- Current page: 220 of 566
- Download datasheet (23Mb)
8271C–AVR–08/10
• Different masters may use different SCL frequencies. A scheme must be devised to
The wired-ANDing of the bus lines is used to solve both these problems. The serial clocks from
all masters will be wired-ANDed, yielding a combined clock with a high period equal to the one
from the Master with the shortest high period. The low period of the combined clock is equal to
the low period of the Master with the longest low period. Note that all masters listen to the SCL
line, effectively starting to count their SCL high and low time-out periods when the combined
SCL line goes high or low, respectively.
Figure 21-7. SCL Synchronization Between Multiple Masters
Arbitration is carried out by all masters continuously monitoring the SDA line after outputting
data. If the value read from the SDA line does not match the value the Master had output, it has
lost the arbitration. Note that a Master can only lose arbitration when it outputs a high SDA value
while another Master outputs a low value. The losing Master should immediately go to Slave
mode, checking if it is being addressed by the winning Master. The SDA line should be left high,
but losing masters are allowed to generate a clock signal until the end of the current data or
address packet. Arbitration will continue until only one Master remains, and this may take many
bits. If several masters are trying to address the same Slave, arbitration will continue into the
data packet.
ATmega48A/48PA/88A/88PA/168A/168PA/328/328
masters have started transmission at the same time should not be detectable to the slaves, i.e.
the data being transferred on the bus must not be corrupted.
synchronize the serial clocks from all masters, in order to let the transmission proceed in a
lockstep fashion. This will facilitate the arbitration process.
SCL from
SCL from
Master A
Master B
SCL Bus
Line
TA
Counting Low Period
low
Masters Start
TB
low
TA
Counting High Period
high
Masters Start
TB
high
220
Related parts for ATMEGA328-AU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 44-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 40DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ 5V 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ IND 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ IND 44-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32KB FLASH 16MHZ 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32KB FLASH 16MHZ 44QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 32K FLASH 16MHZ 44-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ COM 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ COM 44-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 32K 16MHZ COM 44-TQFP
Manufacturer:
Atmel
Datasheet: