ATMEGA8-16AJ Atmel, ATMEGA8-16AJ Datasheet - Page 50

• Manufacturer Part Number: ATMEGA8-16AJ
• Description: IC MCU AVR 8K 5V 16MHZ 32-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8-16AJ

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

50
ATmega8(L)
• Bit 0 – IVCE: Interrupt Vector Change Enable
The IVCE bit must be written to logic one to enable change of the IVSEL bit. IVCE is cleared by
hardware four cycles after it is written or when IVSEL is written. Setting the IVCE bit will disable
interrupts, as explained in the IVSEL description above. See Code Example below.
Assembly Code Example
C Code Example
Move_interrupts:
void Move_interrupts(void)
{
}
; Enable change of Interrupt Vectors
ldi r16, (1<<IVCE)
out GICR, r16
; Move interrupts to boot Flash section
ldi r16, (1<<IVSEL)
out GICR, r16
ret
/* Enable change of Interrupt Vectors */
GICR = (1<<IVCE);
/* Move interrupts to boot Flash section */
GICR = (1<<IVSEL);
2486Z–AVR–02/11