ATmega329 Atmel Corporation, ATmega329 Datasheet - Page 22

• Manufacturer Part Number: ATmega329
• Manufacturer: Atmel Corporation

Specifications of ATmega329

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 17
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Segment Lcd: 100
• 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): 2
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

7.5
7.5.1
7.5.2
7.5.3
22
Register Description
ATmega329/3290/649/6490
EEARH and EEARL – The EEPROM Address Register
EEDR – The EEPROM Data Register
EECR – The EEPROM Control Register
• Bits 15:11 – Reserved Bits
These bits are reserved bits in the ATmega329/3290/649/6490 and will always read as zero.
• Bits 10:0 – EEAR10:0: EEPROM Address
The EEPROM Address Registers – EEARH and EEARL specify the EEPROM address in the
1/2K bytes EEPROM space. The EEPROM data bytes are addressed linearly between 0 and
1023/2047. The initial value of EEAR is undefined. A proper value must be written before the
EEPROM may be accessed.
Note:
• Bits 7:0 – EEDR7:0: EEPROM Data
For the EEPROM write operation, the EEDR Register contains the data to be written to the
EEPROM in the address given by the EEAR Register. For the EEPROM read operation, the
EEDR contains the data read out from the EEPROM at the address given by EEAR.
• Bits 7:4 – Reserved Bits
These bits are reserved bits in the ATmega329/3290/649/6490 and will always read as zero.
• Bit 3 – EERIE: EEPROM Ready Interrupt Enable
Writing EERIE to one enables the EEPROM Ready Interrupt if the I bit in SREG is set. Writing
EERIE to zero disables the interrupt. The EEPROM Ready interrupt generates a constant inter-
rupt when EEWE is cleared.
• Bit 2 – EEMWE: EEPROM Master Write Enable
The EEMWE bit determines whether setting EEWE to one causes the EEPROM to be written.
When EEMWE is set, setting EEWE within four clock cycles will write data to the EEPROM at
Bit
0x22 (0x42)
0x21 (0x41)
Read/Write
Initial Value
Bit
0x20 (0x40)
Read/Write
Initial Value
Bit
0x1F (0x3F)
Read/Write
Initial Value
EEAR10 is only valid for ATmega649 and ATmega6490.
EEAR7
MSB
R/W
R/W
15
7
0
R
X
–
7
0
R
7
–
0
EEAR6
R/W
R/W
14
6
0
R
X
–
6
0
R
6
–
0
EEAR5
R/W
R/W
13
R
5
0
–
5
0
X
R
5
–
0
EEAR4
R/W
R/W
12
R
4
0
–
4
0
X
R
4
–
0
EEAR3
R/W
R/W
EERIE
11
R
3
0
R/W
–
3
0
X
3
0
EEAR10
EEAR2
EEMWE
R/W
R/W
R/W
10
2
0
2
X
X
R/W
2
0
EEAR9
EEAR1
R/W
R/W
R/W
EEWE
X
X
1
0
9
1
R/W
1
X
EEAR8
EEAR0
LSB
R/W
R/W
R/W
EERE
X
X
8
0
0
0
R/W
0
0
EEARH
EEARL
EEDR
2552K–AVR–04/11
EECR