• Bit 0 – TOIE2: Timer/Counter2 Overflow Interrupt Enable
When the TOIE2 bit is written to one and the I-bit in the Status Register is set (one), the
Timer/Counter2 Overflow interrupt is enabled. The corresponding interrupt is executed if
an overflow in Timer/Counter2 occurs, i.e., when the TOV2 bit is set in the
Timer/Counter2 Interrupt Flag Register – TIFR2.
Timer/Counter2 Interrupt Flag
Register – TIFR2
Bit
7
–
6
–
5
–
4
–
3
–
2
OCF2B
R/W
0
1
OCF2A
R/W
0
0
TOV2
R/W
0
TIFR2
Read/Write
Initial Value
R
0
R
0
R
0
R
0
R
0
• Bit 2 – OCF2B: Output Compare Flag 2 B
The OCF2B bit is set (one) when a compare match occurs between the Timer/Counter2
and the data in OCR2B – Output Compare Register2. OCF2B is cleared by hardware
when executing the corresponding interrupt handling vector. Alternatively, OCF2B is
cleared by writing a logic one to the flag. When the I-bit in SREG, OCIE2B
(Timer/Counter2 Compare match Interrupt Enable), and OCF2B are set (one), the
Timer/Counter2 Compare match Interrupt is executed.
• Bit 1 – OCF2A: Output Compare Flag 2 A
The OCF2A bit is set (one) when a compare match occurs between the Timer/Counter2
and the data in OCR2A – Output Compare Register2. OCF2A is cleared by hardware
when executing the corresponding interrupt handling vector. Alternatively, OCF2A is
cleared by writing a logic one to the flag. When the I-bit in SREG, OCIE2A
(Timer/Counter2 Compare match Interrupt Enable), and OCF2A are set (one), the
Timer/Counter2 Compare match Interrupt is executed.
• Bit 0 – TOV2: Timer/Counter2 Overflow Flag
The TOV2 bit is set (one) when an overflow occurs in Timer/Counter2. TOV2 is cleared
by hardware when executing the corresponding interrupt handling vector. Alternatively,
TOV2 is cleared by writing a logic one to the flag. When the SREG I-bit, TOIE2A
(Timer/Counter2 Overflow Interrupt Enable), and TOV2 are set (one), the
Timer/Counter2 Overflow interrupt is executed. In PWM mode, this bit is set when
Timer/Counter2 changes counting direction at 0x00.
192
ATmega640/1280/1281/2560/2561
2549A–AVR–03/05
ATMEL [ ATMEL ]
