ATmega8A Atmel Corporation, ATmega8A Datasheet - Page 45

• Manufacturer Part Number: ATmega8A
• Manufacturer: Atmel Corporation

Specifications of ATmega8A

• Flash (kbytes): 8 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 23
• Ext Interrupts: 2
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• 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 85
• 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
• Pwm Channels: 3
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

11. Interrupts
11.1
8159D–AVR–02/11
Interrupt Vectors in ATmega8A
This section describes the specifics of the interrupt handling performed by the ATmega8A. For a
general explanation of the AVR interrupt handling, refer to
page
Table 11-1.
Notes:
Table 11-2
BOOTRST and IVSEL settings. If the program never enables an interrupt source, the Interrupt
Vectors are not used, and regular program code can be placed at these locations. This is also
the case if the Reset Vector is in the Application section while the Interrupt Vectors are in the
boot section or vice versa.
Vector No.
13.
10
11
12
13
14
15
16
17
18
19
1
2
3
4
5
6
7
8
9
1. When the BOOTRST Fuse is programmed, the device will jump to the Boot Loader address at
2. When the IVSEL bit in GICR is set, Interrupt Vectors will be moved to the start of the boot
reset, see
Flash section. The address of each Interrupt Vector will then be the address in this table added
to the start address of the boot Flash section.
shows reset and Interrupt Vectors placement for the various combinations of
Reset and Interrupt Vectors
Address
Program
0x000
0x00C
0x00D
0x00A
0x00B
0x00E
0x00F
0x001
0x002
0x003
0x004
0x005
0x006
0x007
0x008
0x009
0x010
0x011
0x012
“Boot Loader Support – Read-While-Write Self-Programming” on page
(1)
(2)
Source
RESET
INT0
INT1
TIMER2 COMP
TIMER2 OVF
TIMER1 CAPT
TIMER1 COMPA
TIMER1 COMPB
TIMER1 OVF
TIMER0 OVF
SPI, STC
USART, RXC
USART, UDRE
USART, TXC
ADC
EE_RDY
ANA_COMP
TWI
SPM_RDY
Interrupt Definition
External Pin, Power-on Reset, Brown-out Reset,
and Watchdog Reset
External Interrupt Request 0
External Interrupt Request 1
Timer/Counter2 Compare Match
Timer/Counter2 Overflow
Timer/Counter1 Capture Event
Timer/Counter1 Compare Match A
Timer/Counter1 Compare Match B
Timer/Counter1 Overflow
Timer/Counter0 Overflow
Serial Transfer Complete
USART, Rx Complete
USART Data Register Empty
USART, Tx Complete
ADC Conversion Complete
EEPROM Ready
Analog Comparator
Two-wire Serial Interface
Store Program Memory Ready
“Reset and Interrupt Handling” on
ATmega8A
212.
45