Datasheet

27
8284D–AVR–6/11
ATmega169A/PA/329A/PA/3290A/PA/649A/P/6490A/P
8.6 Register Description
8.6.1 EEARH and EEARL – EEPROM Address Register ATmega169A/169PA
• Bits 15:9 – Reserved
These bits are reserved and will always be read as zero.
• Bits 8:0 – EEAR8:0: EEPROM Address
The EEPROM Address Registers – EEARH and EEARL specify the EEPROM address in the
512 bytes EEPROM space. The EEPROM data bytes are addressed linearly between 0 and
511. The initial value of EEAR is undefined. A proper value must be written before the EEPROM
may be accessed.
8.6.2 EEARH and EEARL – EEPROM Address Register
ATmega329A/329PA/3290A/3290PA/649A/649P/6490A/6490P
• Bits 15:11 – Reserved
These bits are reserved bits in the
ATmega329A/329PA/3290A/3290PA/649A/649P/6490A/6490P 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: 1. EEAR10 is only valid for ATmega649A/649P/6490A/6490P.
Bit 151413121110 9 8
0x22 (0x42)
– – – – – – – EEAR8 EEARH
0x21 (0x41) EEAR7 EEAR6 EEAR5 EEAR4 EEAR3 EEAR2 EEAR1 EEAR0 EEARL
765 4 3 2 1 0
Read/Write R R R R R R R R/W
R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 X
XXX X X X X X
Bit 1514131211 10 9 8
0x22 (0x42)
– – – – –EEAR10
(1)
EEAR9 EEAR8 EEARH
0x21 (0x41) EEAR7 EEAR6 EEAR5 EEAR4 EEAR3 EEAR2 EEAR1 EEAR0 EEARL
76543 2 1 0
Read/WriteRRRRRR/WR/WR/W
R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 X X X
XXXXX X X X