Rainbow Electronics ATmega64L - Manual (Page 80)

80
ATmega16(L)
2466B–09/01
Output Compare Register –
OCR0
The Output Compare Register 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 OC0 pin.
Timer/Counter Interrupt Mask
Register – TIMSK
• Bit 1 - OCIE0: Timer/Counter0 Output Compare Match Interrupt Enable
When the OCIE0 bit is written to one, and the I-bit in the Status Register is set (one), the
Timer/Counter0 Compare Match interrupt is enabled. The corresponding interrupt is
executed if a compare match in Timer/Counter0 occurs, i.e., when the OCF0 bit is set in
the Timer/Counter Interrupt Flag Register - TIFR.
• 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 (one), 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 Interrupt Flag Register – TIFR.
Timer/Counter Interrupt Flag
Register – TIFR
• Bit 1 - OCF0: Output Compare Flag 0
The OCF0 bit is set (one) when a compare match occurs between the Timer/Counter0
and the data in OCR0 - Output Compare Register0. OCF0 is cleared by hardware when
executing the corresponding interrupt handling vector. Alternatively, OCF0 is cleared by
writing a logic one to the flag. When the I-bit in SREG, OCIE0 (Timer/Counter0 Com-
pare match Interrupt Enable), and OCF0 are set (one), the Timer/Counter0 Compare
match Interrupt is executed.
• Bit 0 - TOV0: Timer/Counter0 Overflow Flag
The bit TOV0 is set (one) 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
(Time r/Cou nter0 Ove rf lo w In terrupt Enab le), and TOV0 a re set (one ), th e
Timer/Counter0 Overflow interrupt is executed. In phase correct PWM mode, this bit is
set when Timer/Counter0 changes counting direction at $00.
Bit 7 6 5 4 3 2 1 0
OCR0[7:0] OCR0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
OCIE2 TOIE2 TICIE1 OCIE1A OCIE1B TOIE1 OCIE0 TOIE0 TIMSK
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
OCF2 TOV2 ICF1 OCF1A OCF1B TOV1 OCF0 TOV0 TIFR
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0