ATMEGA8A-MUR Atmel, ATMEGA8A-MUR Datasheet - Page 181
ATMEGA8A-MUR
Manufacturer Part Number
ATMEGA8A-MUR
Description
MCU AVR 8KB FLASH 16MHZ 32QFN
Manufacturer
Atmel
Series
AVR® ATmegar
Datasheet
1.ATMEGA8A-MU.pdf
(308 pages)
Specifications of ATMEGA8A-MUR
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
23
Program Memory Size
8KB (4K 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
*
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
- Current page: 181 of 308
- Download datasheet (6Mb)
8159D–AVR–02/11
Figure 20-13. Data Transfer in Master Receiver Mode
A START condition is sent by writing the following value to TWCR:
TWEN must be written to one to enable the Two-wire Serial Interface, TWSTA must be written to
one to transmit a START condition and TWINT must be set to clear the TWINT Flag. The TWI
will then test the Two-wire Serial Bus and generate a START condition as soon as the bus
becomes free. After a START condition has been transmitted, the TWINT Flag is set by hard-
ware, and the status code in TWSR will be 0x08 (See
SLA+R must be transmitted. This is done by writing SLA+R to TWDR. Thereafter the TWINT bit
should be cleared (by writing it to one) to continue the transfer. This is accomplished by writing
the following value to TWCR:
When SLA+R have been transmitted and an acknowledgement bit has been received, TWINT is
set again and a number of status codes in TWSR are possible. Possible status codes in Master
mode are 0x38, 0x40, or 0x48. The appropriate action to be taken for each of these status codes
is detailed in
Flag is set high by hardware. This scheme is repeated until the last byte has been received.
After the last byte has been received, the MR should inform the ST by sending a NACK after the
last received data byte. The transfer is ended by generating a STOP condition or a repeated
START condition. A STOP condition is generated by writing the following value to TWCR:
A REPEATED START condition is generated by writing the following value to TWCR:
After a repeated START condition (state 0x10) the Two-wire Serial Interface can access the
same Slave again, or a new Slave without transmitting a STOP condition. Repeated START
enables the Master to switch between Slaves, Master Transmitter mode and Master Receiver
mode without losing control over the bus.
TWCR
value
TWCR
value
TWCR
value
TWCR
value
SDA
SCL
Table
TWINT
TWINT
TWINT
TWINT
1
1
1
1
20-4. Received data can be read from the TWDR Register when the TWINT
Device 1
RECEIVER
MASTER
TWEA
TWEA
TWEA
TWEA
X
X
X
X
TRANSMITTER
Device 2
SLAVE
TWSTA
TWSTA
TWSTA
TWSTA
1
0
0
1
Device 3
TWSTO
TWSTO
TWSTO
TWSTO
0
0
1
0
........
Table
TWWC
TWWC
TWWC
TWWC
Device n
X
X
X
X
20-3). In order to enter MR mode,
V
CC
TWEN
TWEN
TWEN
TWEN
1
1
1
1
R1
ATmega8A
R2
–
0
–
0
–
0
–
0
TWIE
TWIE
TWIE
TWIE
X
X
X
X
181
Related parts for ATMEGA8A-MUR
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
MCU AVR 8K FLASH 16MHZ 32-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 8K FLASH 16MHZ 28-PDIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 8KB FLASH 16MHZ 32TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
8-bit Microcontrollers - MCU AVR 8KB FL 512B EE 1KB SRAM 16 MHZ GRN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 8K 16MHZ 5V 32TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 8K 16MHZ 5V 32-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 8K 16MHZ 5V 28DIP
Manufacturer:
Atmel
Datasheet: