A000048 Arduino, A000048 Datasheet - Page 224
![ATMEGA328 MCU IC W/ Arduino UNO Bootloader](/photos/18/99/189989/4243185_sml.jpg)
A000048
Manufacturer Part Number
A000048
Description
ATMEGA328 MCU IC W/ Arduino UNO Bootloader
Manufacturer
Arduino
Series
-r
Specifications of A000048
Accessory Type
Pre-Programed IC
Features
Powered Via USB Connection, AC-to-DC Adapter, Power Jack, ICSP Header
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
-
For Use With
ATmega328 Microcontrollers
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
- Current page: 224 of 566
- Download datasheet (23Mb)
21.6
Figure 21-10. Interfacing the Application to the TWI in a Typical Transmission
8271C–AVR–08/10
Using the TWI
writes to TWCR to
TWI bus
transmission of
1. Application
START condition sent
Status code indicates
START
initiate
2. TWINT set.
START
TWDR, and loads appropriate control
3. Check TWSR to see if START was
signals into TWCR, makin sure that
sent. Application loads SLA+W into
• After the TWI has transmitted SLA+R/W.
• After the TWI has transmitted an address byte.
• After the TWI has lost arbitration.
• After the TWI has been addressed by own slave address or general call.
• After the TWI has received a data byte.
• After a STOP or REPEATED START has been received while still addressed as a Slave.
• When a bus error has occurred due to an illegal START or STOP condition.
The AVR TWI is byte-oriented and interrupt based. Interrupts are issued after all bus events, like
reception of a byte or transmission of a START condition. Because the TWI is interrupt-based,
the application software is free to carry on other operations during a TWI byte transfer. Note that
the TWI Interrupt Enable (TWIE) bit in TWCR together with the Global Interrupt Enable bit in
SREG allow the application to decide whether or not assertion of the TWINT Flag should gener-
ate an interrupt request. If the TWIE bit is cleared, the application must poll the TWINT Flag in
order to detect actions on the TWI bus.
When the TWINT Flag is asserted, the TWI has finished an operation and awaits application
response. In this case, the TWI Status Register (TWSR) contains a value indicating the current
state of the TWI bus. The application software can then decide how the TWI should behave in
the next TWI bus cycle by manipulating the TWCR and TWDR Registers.
Figure 21-10
this example, a Master wishes to transmit a single data byte to a Slave. This description is quite
abstract, a more detailed explanation follows later in this section. A simple code example imple-
menting the desired behavior is also presented.
1. The first step in a TWI transmission is to transmit a START condition. This is done by
ATmega48A/48PA/88A/88PA/168A/168PA/328/328
and TWSTA is written to zero.
TWINT is written to one,
writing a specific value into TWCR, instructing the TWI hardware to transmit a START
condition. Which value to write is described later on. However, it is important that the
SLA+W
is a simple example of how the application can interface to the TWI hardware. In
Status code indicates
SLA+W sent, ACK
4. TWINT set.
received
A
Application loads data into TWDR, and
5. Check TWSR to see if SLA+W was
loads appropriate control signals into
TWCR, making sure that TWINT is
sent and ACK received.
written to one
Data
data sent, ACK received
Status code indicates
6. TWINT set.
A
making sure that TWINT is written to one
7. Check TWSR to see if data was sent
Application loads appropriate control
signals to send STOP into TWCR,
STOP
and ACK received.
TWINT set
Indicates
224
Related parts for A000048
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![A000082](/images/no-image3.png)
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO UNO PROTO PCB REV 3
Manufacturer:
Arduino
![A000083](/images/no-image3.png)
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO SHIELD PROTO KIT REV 3
Manufacturer:
Arduino
![A000081](/images/no-image3.png)
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO MEGA PROTO KIT REV 3
Manufacturer:
Arduino
![A000080](/images/no-image3.png)
Part Number:
Description:
Daughter Cards & OEM Boards ARDUINO MEGA PROTO PCB REV 3
Manufacturer:
Arduino
![K000007](/images/no-image3.png)
Part Number:
Description:
Development Boards & Kits - AVR ARDUINO STARTER KIT W/ UNO REV3
Manufacturer:
Arduino
![A000064](/images/no-image3.png)
Part Number:
Description:
RF Development Tools ARDUINO SHIELD WIRELESS PROTO
Manufacturer:
Arduino
Datasheet:
![A000065](/images/no-image3.png)
Part Number:
Description:
RF Development Tools ARDUINO SHIELD WIRELESS WITH SD
Manufacturer:
Arduino
Datasheet:
![A000035](/photos/15/87/158783/gettingstarted_tmb.jpg)
Part Number:
Description:
Development Software Getting started w/Arduino
Manufacturer:
Arduino
![A000031](/photos/15/88/158818/arduinoethernetshield_tmb.jpg)
Part Number:
Description:
Ethernet Modules & Development Tools Ethernet Shield for Arduino
Manufacturer:
Arduino
![LILYPAD](/photos/15/93/159314/lilypad_3_tmb.jpg)
Part Number:
Description:
MCU, MPU & DSP Development Tools LilyPad Arduino Main Board
Manufacturer:
Arduino
![A000005](/photos/24/11/241196/13t9275-30-web_tmb.jpg)
Part Number:
Description:
ARDUINO NANO Board
Manufacturer:
Arduino
Datasheet:
![A000056](/images/no-image3.png)
Part Number:
Description:
Ethernet Modules & Development Tools ETHERNET SHEILD PoE FOR ARDUINO
Manufacturer:
Arduino
Datasheet:
![A000007](/images/no-image3.png)
Part Number:
Description:
KIT XBEE/SHIELD ARDUINO
Manufacturer:
Arduino
Datasheet:
![X000001](/images/no-image3.png)
Part Number:
Description:
Memory Cards MICRO SD CARD 1GB WITH SD ADAPTER
Manufacturer:
Arduino