Rainbow-electronics ATmega64C1 Manuel d'utilisateur télécharger pdf (Page 105)

105

7647A–AVR–02/08

ATmega32/64/M1/C1

overflow in Timer/Counter0 occurs, i.e., when the TOV0 bit is set in the Timer/Counter 0 Inter-

rupt Flag Register – TIFR0.

12.8.7 Timer/Counter 0 Interrupt Flag Register – TIFR0

• Bits 7..3 – Res: Reserved Bits

These bits are reserved bits in the ATmega32/64/M1/C1 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 cor-

responding 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 cor-

responding 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 0 – TOV0: Timer/Counter0 Overflow Flag

The bit TOV0 is set when an overflow occurs in Timer/Counter0. TOV0 is cleared by hardware

when executing the corresponding interrupt handling vector. Alternatively, TOV0 is cleared by

writing a logic one to the flag. When the SREG I-bit, TOIE0 (Timer/Counter0 Overflow Interrupt

Enable), and TOV0 are set, the Timer/Counter0 Overflow interrupt is executed.

The setting of this flag is dependent of the WGM02:0 bit setting. Refer to Table 12-8, “Waveform

Generation Mode Bit Description” on page 102.

Bit 76543210

–––––OCF0BOCF0ATOV0TIFR0

Read/Write RRRRRR/WR/WR/W

Initial Value00000000

1 2 ... 100 101 102 103 104 105 106 107 108 109 110 ... 365 366

Pas de commentaire

Rainbow-electronics ATmega64C1 Manuel d'utilisateur Page 105