ATMEGA2561V ATMEL [ATMEL Corporation], ATMEGA2561V Datasheet - Page 135

• Manufacturer Part Number: ATMEGA2561V
• Description: 8-bit Microcontroller with 64K/128K/256K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

TIMSK0 – Timer/Counter
Interrupt Mask Register
TIFR0 – Timer/Counter 0
Interrupt Flag Register
2549K–AVR–01/07
• Bits 7:3, 0 – Res: Reserved Bits
These bits are reserved bits and will always read as zero.
• Bit 2 – OCIE0B: Timer/Counter Output Compare Match B Interrupt Enable
When the OCIE0B bit is written to one, and the I-bit in the Status Register is set, the
Timer/Counter Compare Match B interrupt is enabled. The corresponding interrupt is
executed if a Compare Match in Timer/Counter occurs, i.e., when the OCF0B bit is set in
the Timer/Counter Interrupt Flag Register – TIFR0.
• Bit 1 – OCIE0A: Timer/Counter0 Output Compare Match A Interrupt Enable
When the OCIE0A bit is written to one, and the I-bit in the Status Register is set, the
Timer/Counter0 Compare Match A interrupt is enabled. The corresponding interrupt is
executed if a Compare Match in Timer/Counter0 occurs, i.e., when the OCF0A bit is set
in the Timer/Counter 0 Interrupt Flag Register – TIFR0.
• Bit 0 – TOIE0: Timer/Counter0 Overflow Interrupt Enable
When the TOIE0 bit is written to one, and the I-bit in the Status Register is set, the
Timer/Counter0 Overflow interrupt is enabled. The corresponding interrupt is executed if
an overflow in Timer/Counter0 occurs, i.e., when the TOV0 bit is set in the
Timer/Counter 0 Interrupt Flag Register – TIFR0.
• Bits 7:3, 0 – Res: Reserved Bits
These bits are reserved bits and will always read as zero.
• Bit 2 – OCF0B: Timer/Counter 0 Output Compare B Match Flag
The OCF0B bit is set when a Compare Match occurs between the Timer/Counter and
the data in OCR0B – Output Compare Register0 B. OCF0B is cleared by hardware
when executing the corresponding interrupt handling vector. Alternatively, OCF0B is
cleared by writing a logic one to the flag. When the I-bit in SREG, OCIE0B
(Timer/Counter Compare B Match Interrupt Enable), and OCF0B are set, the
Timer/Counter Compare Match Interrupt is executed.
• Bit 1 – OCF0A: Timer/Counter 0 Output Compare A Match Flag
The OCF0A bit is set when a Compare Match occurs between the Timer/Counter0 and
the data in OCR0A – Output Compare Register0. OCF0A is cleared by hardware when
executing the corresponding interrupt handling vector. Alternatively, OCF0A is cleared
by writing a logic one to the flag. When the I-bit in SREG, OCIE0A (Timer/Counter0
Compare Match Interrupt Enable), and OCF0A are set, the Timer/Counter0 Compare
Match Interrupt is executed.
Bit
(0x6E)
Read/Write
Initial Value
Bit
0x15 (0x35)
Read/Write
Initial Value
R
R
7
–
0
7
–
0
ATmega640/1280/1281/2560/2561
R
R
6
–
0
6
–
0
R
R
5
–
0
5
–
0
R
R
4
–
0
4
–
0
R
3
–
R
0
3
–
0
OCIE0B
OCF0B
R/W
R/W
2
0
2
0
OCF0A
OCIE0A
R/W
R/W
1
0
1
0
TOV0
TOIE0
R/W
R/W
0
0
0
0
TIMSK0
TIFR0
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