General interrupt flag register – gifr, Atmega162/v – Rainbow Electronics ATmega162V User Manual
Page 86

86
ATmega162/V
2513E–AVR–09/03
General Interrupt Flag
Register – GIFR
• Bit 7 – INTF1: External Interrupt Flag 1
When an edge or logic change on the INT1 pin triggers an interrupt request, INTF1
becomes set (one). If the I-bit in SREG and the INT1 bit in GICR are set (one), the MCU
will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt
routine is executed. Alternatively, the flag can be cleared by writing a logical one to it.
This flag is always cleared when INT1 is configured as a level interrupt.
• Bit 6 – INTF0: External Interrupt Flag 0
When an edge or logic change on the INT0 pin triggers an interrupt request, INTF0
becomes set (one). If the I-bit in SREG and the INT0 bit in GICR are set (one), the MCU
will jump to the corresponding Interrupt Vector. The flag is cleared when the interrupt
routine is executed. Alternatively, the flag can be cleared by writing a logical one to it.
This flag is always cleared when INT0 is configured as a level interrupt.
• Bit 5 – INTF2: External Interrupt Flag 2
When an event on the INT2 pin triggers an interrupt request, INTF2 becomes set (one).
If the I-bit in SREG and the INT2 bit in GICR are set (one), the MCU will jump to the cor-
responding Interrupt Vector. The flag is cleared when the interrupt routine is executed.
Alternatively, the flag can be cleared by writing a logical one to it. Note that when enter-
ing some sleep modes with the INT2 interrupt disabled, the input buffer on this pin will
be disabled. This may cause a logic change in internal signals which will set the INTF2
flag. See “Digital Input Enable and Sleep Modes” on page 66 for more information.
• Bit 4 – PCIF1: Pin Change Interrupt Flag 1
When a logic change on any PCINT15..8 pin triggers an interrupt request, PCIF1
becomes set (one). If the I-bit in SREG and the PCIE1 bit in GICR are set (one), the
MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the inter-
rupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to
it.
• Bit 3 – PCIF0: Pin Change Interrupt Flag 0
When a logic change on any PCINT7..0 pin triggers an interrupt request, PCIF0
becomes set (one). If the I-bit in SREG and the PCIE0 bit in GICR are set (one), the
MCU will jump to the corresponding Interrupt Vector. The flag is cleared when the inter-
rupt routine is executed. Alternatively, the flag can be cleared by writing a logical one to
it.
Bit
7
6
5
4
3
2
1
0
INTF1
INTF0
INTF2
PCIF1
PCIF0
–
–
–
GIFR
Read/Write
R/W
R/W
R/W
R/W
R/W
R
R
R
Initial Value
0
0
0
0
0
0
0
0