atmega3250v-8auatmega325v-8ai ATMEL Corporation, atmega3250v-8auatmega325v-8ai Datasheet - Page 57

• Manufacturer Part Number: atmega3250v-8auatmega325v-8ai
• Description: Atmega3250 8-bit Microcontroller With In-system Programmable Flash
• Manufacturer: ATMEL Corporation

13.2.4
13.2.5
2570L–AVR–08/07
PCMSK3 – Pin Change Mask Register 3
PCMSK2 – Pin Change Mask Register 2
corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alter-
natively, the flag can be cleared by writing a logical one to it.
This bit is reserved bit in ATmega325/645 and will always be read as zero.
• Bit 6– PCIF2: Pin Change Interrupt Flag 2
When a logic change on any PCINT24..16 pin triggers an interrupt request, PCIF2 becomes set
(one). If the I-bit in SREG and the PCIE2 bit in EIMSK are set (one), the MCU will jump to the
corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alter-
natively, the flag can be cleared by writing a logical one to it.
This bit is reserved bit in ATmega325/645 and will always be read as zero.
• Bit 5– 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 EIMSK are set (one), the MCU will jump to the
corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alter-
natively, the flag can be cleared by writing a logical one to it.
• Bit 4– 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 EIMSK are set (one), the MCU will jump to the
corresponding Interrupt Vector. The flag is cleared when the interrupt routine is executed. Alter-
natively, the flag can be cleared by writing a logical one to it.
• Bit 0 – 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 EIMSK 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. This flag is always cleared
when INT0 is configured as a level interrupt.
• Bit 6:0 – PCINT30:24: Pin Change Enable Mask 30:24
Each PCINT30:24-bit selects whether pin change interrupt is enabled on the corresponding I/O
pin. If PCINT30:24 is set and the PCIE3 bit in EIMSK is set, pin change interrupt is enabled on
the corresponding I/O pin. If PCINT30:24 is cleared, pin change interrupt on the corresponding
I/O pin is disabled.
Bit
(0x6D)
Read/Write
Initial
Value
Bit
(0x73)
Read/Write
Initial Value
PCINT23
R/W
7
0
R
7
–
0
PCINT22
PCINT30
R/W
R/W
6
0
6
0
(1)
(1)
PCINT21
PCINT29
R/W
R/W
5
0
5
0
PCINT20
PCINT28
R/W
R/W
4
0
4
0
ATmega325/3250/645/6450
PCINT19
PCINT27
R/W
R/W
3
0
3
0
PCINT18
PCINT26
R/W
R/W
2
0
2
0
PCINT17
PCINT25
R/W
R/W
1
0
1
0
PCINT16
PCINT24
R/W
R/W
0
0
0
0
PCMSK2
PCMSK3
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