ATMEGA8U2_1 ATMEL [ATMEL Corporation], ATMEGA8U2_1 Datasheet - Page 10

• Manufacturer Part Number: ATMEGA8U2_1
• Description: 8-bit Microcontroller with 8/16/32K Bytes of ISP Flash and USB Controller
• Manufacturer: ATMEL [ATMEL Corporation]

Note:
7799CS–AVR–12/09
0x0D (0x2D)
0x0C (0x2C)
0x1A (0x3A)
0x0E (0x2E)
0x0B (0x2B)
0x0A (0x2A)
Address
0x19 (0x39)
0x18 (0x38)
0x17 (0x37)
0x16 (0x36)
0x15 (0x35)
0x14 (0x34)
0x13 (0x33)
0x12 (0x32)
0x11 (0x31)
0x10 (0x30)
0x0F (0x2F)
0x09 (0x29)
0x08 (0x28)
0x07 (0x27)
0x06 (0x26)
0x05 (0x25)
0x04 (0x24)
0x03 (0x23)
0x02 (0x22)
0x01 (0x21)
0x00 (0x20)
1. For compatibility with future devices, reserved bits should be written to zero if accessed. Moreover reserved bits are not
2. I/O registers within the address range $00 - $1F are directly bit-accessible using the SBI and CBI instructions. In these reg-
3. Some of the status flags are cleared by writing a logical one to them. Note that the CBI and SBI instructions will operate on
4. When using the I/O specific commands IN and OUT, the I/O addresses $00 - $3F must be used. When addressing I/O reg-
guaranteed to be read as “0”. Reserved I/O memory addresses should never be written.
isters, the value of single bits can be checked by using the SBIS and SBIC instructions.
all bits in the I/O register, writing a one back into any flag read as set, thus clearing the flag. The CBI and SBI instructions
work with registers 0x00 to 0x1F only.
isters as data space using LD and ST instructions, $20 must be added to these addresses. The ATmega8U2/16U2/32U2 is
a complex microcontroller with more peripheral units than can be supported within the 64 location reserved in Opcode for
the IN and OUT instructions. For the Extended I/O space from $60 - $1FF in SRAM, only the ST/STS/STD and LD/LDS/LDD
instructions can be used.
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Name
PORTD
PORTC
PORTB
DDRD
DDRC
DDRB
TIFR1
TIFR0
PIND
PINC
PINB
PORTD7
PORTC7
PORTB7
Bit 7
PIND7
PINC7
PINB7
DDD7
DDC7
DDB7
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD6
PORTC6
PORTB6
Bit 6
PIND6
PINC6
PINB6
DDD6
DDC6
DDB6
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD5
PORTC5
PORTB5
PIND5
PINC5
Bit 5
PINB5
DDD5
DDC5
DDB5
ICF1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD4
PORTC4
PORTB4
Bit 4
PIND4
PINC4
PINB4
DDD4
DDC4
DDB4
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD3
PORTB3
OCF1C
Bit 3
PIND3
PINB3
DDD3
DDB3
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD2
PORTC2
PORTB2
OCF1B
OCF0B
ATmega8U2/16U2/32U2
Bit 2
PIND2
PINC2
PINB2
DDD2
DDC2
DDB2
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD1
PORTC1
PORTB1
OCF1A
OCF0A
PIND1
PINC1
Bit 1
DDD1
DDC1
PINB1
DDB1
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
PORTD0
PORTC0
PORTB0
Bit 0
PIND0
PINC0
PINB0
TOV1
TOV0
DDD0
DDC0
DDB0
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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