Datasheet
10
8265CS–AVR–03/12
ATtiny87
Notes: 1. Address bits exceeding EEAMSB (Table 21-8 on page 227) are don’t care.
2. For compatibility with future devices, reserved bits should be written to zero if accessed. Reserved I/O memory addresses
should never be written.
3. I/O Registers within the address range 0x00 - 0x1F are directly bit-accessible using the SBI and CBI instructions. In these
registers, the value of single bits can be checked by using the SBIS and SBIC instructions.
4. Some of the status flags are cleared by writing a logical one to them. Note that, unlike most other AVRs, the CBI and SBI
instructions will only operate on the specified bit, and can therefore be used on registers containing such status flags. The
CBI and SBI instructions work with registers 0x00 to 0x1F only.
5. When using the I/O specific commands IN and OUT, the I/O addresses 0x00 - 0x3F must be used. When addressing I/O
Registers as data space using LD and ST instructions, 0x20 must be added to these addresses. The ATtiny87/167 is a com-
plex 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 0x60 - 0xFF in SRAM, only the ST/STS/STD and LD/LDS/LDD
instructions can be used.
0x1A (0x3A)
Reserved
0x19 (0x39)
Reserved
0x18 (0x38) Reserved
0x17 (0x37) Reserved
0x16 (0x36) TIFR1 – –ICF1– – OCF1B OCF1A TOV1 page 138
0x15 (0x35) TIFR0 – – – – – –OCF0ATOV0 page 104
0x14 (0x34) Reserved
0x13 (0x33) Reserved
0x12 (0x32) PORTCR – – BBMB BBMA – – PUDB PUDA page 75
0x11 (0x31) Reserved
0x10 (0x30) Reserved
0x0F (0x2F) Reserved
0x0E (0x2E) Reserved
0x0D (0x2D) Reserved
0x0C (0x2C) Reserved
0x0B (0x2B) Reserved
0x0A (0x2A) Reserved
0x09 (0x29) Reserved
0x08 (0x28) Reserved
0x07 (0x27) Reserved
0x06 (0x26) Reserved
0x05 (0x25) PORTB PORTB7 PORTB6 PORTB5 PORTB4 PORTB3 PORTB2 PORTB1 PORTB0 page 85
0x04 (0x24) DDRB DDB7 DDB6 DDB5 DDB4 DDB3 DDB2 DDB1 DDB0 page 85
0x03 (0x23) PINB PINB7 PINB6 PINB5 PINB4 PINB3 PINB2 PINB1 PINB0 page 85
0x02 (0x22) PORTA PORTA7 PORTA6 PORTA5 PORTA4 PORTA3 PORTA2 PORTA1 PORTA0 page 85
0x01 (0x21) DDRA DDA7 DDA6 DDA5 DDA4 DDA3 DDA2 DDA1 DDA0 page 85
0x00 (0x20) PINA PINA7 PINA6 PINA5 PINA4 PINA3 PINA2 PINA1 PINA0 page 85
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Page