ATmega168 Automotive Atmel Corporation, ATmega168 Automotive Datasheet - Page 223

• Manufacturer Part Number: ATmega168 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATmega168 Automotive

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 24
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 1
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 150
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

7530I–AVR–02/10
After a repeated START condition (state 0x10) the 2-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 with-
out losing control over the bus.
Table 19-4.
Status
Code
(TWSR)
Prescaler
Bits
are 0
0x08
0x10
0x38
0x40
0x48
0x50
0x58
Status of the 2-wire Se-
rial Bus and 2-wire Seri-
al Interface Hardware
A START condition has
been transmitted
A
condition
transmitted
Arbitration
SLA+R or NOT ACK bit
SLA+R has been trans-
mitted;
ACK has been received
SLA+R has been trans-
mitted;
NOT ACK has been re-
ceived
Data byte has been re-
ceived;
ACK has been returned
Data byte has been re-
ceived;
NOT ACK has been re-
turned
Status codes for Master Receiver Mode
repeated
has
lost
START
been
in
To/from
TWDR
Load SLA+R
Load SLA+R
or
Load SLA+W
No TWDR ac-
tion or
No TWDR ac-
tion
No TWDR ac-
tion or
No TWDR ac-
tion
No TWDR ac-
tion or
No TWDR ac-
tion or
No TWDR ac-
tion
Read
byte or
Read
byte
Read
byte or
Read
byte or
Read
byte
Application Software Response
data
data
data
data
data
ATmega48/88/168 Automotive
ST
A
0
0
0
0
1
0
0
1
0
1
0
0
1
0
1
ST
O
To TWCR
0
0
0
0
0
0
0
0
1
1
0
0
0
1
1
TWI
NT
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
TW
EA
X
X
X
X
X
X
X
X
X
X
X
0
1
0
1
Next Action Taken by TWI Hardware
SLA+R will be transmitted
ACK or NOT ACK will be received
SLA+R will be transmitted
ACK or NOT ACK will be received
SLA+W will be transmitted
Logic will switch to Master Transmitter
mode
2-wire Serial Bus will be released and not
addressed Slave mode will be entered
A START condition will be transmitted
when the bus
becomes free
Data byte will be received and NOT ACK
will be
returned
Data byte will be received and ACK will be
returned
Repeated START will be transmitted
STOP condition will be transmitted and
TWSTO Flag will be reset
STOP condition followed by a START con-
dition will be transmitted and TWSTO Flag
will be reset
Data byte will be received and NOT ACK
will be
returned
Data byte will be received and ACK will be
returned
Repeated START will be transmitted
STOP condition will be transmitted and
TWSTO Flag will be reset
STOP condition followed by a START con-
dition will be transmitted and TWSTO Flag
will be reset
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