Datasheet

109
ATmega16U4/32U4 [DATASHEET]
Atmel-7766J-USB-ATmega16U4/32U4-Datasheet_04/2016
The Output Compare Register B contains an 8-bit value that is continuously compared with the counter value
(TCNT0). A match can be used to generate an Output Compare interrupt, or to generate a waveform output on
the OC0B pin.
13.8.6 Timer/Counter Interrupt Mask Register – TIMSK0
• 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.
13.8.7 Timer/Counter 0 Interrupt Flag Register – TIFR0
• Bits 7..3, 0 – Res: Reserved Bits
These bits are reserved bits in the ATmega16U4/ATmega32U4 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,
Bit 76543 2 10
– – – – – OCIE0B OCIE0A TOIE0 TIMSK0
Read/Write R R R R R R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
–––––OCF0BOCF0ATOV0 TIFR0
Read/Write R R R R R R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0