attiny25v ATMEL Corporation, attiny25v Datasheet - Page 96

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

12.3.8
96
ATtiny25/45/85
TIFR – Timer/Counter Interrupt Flag Register
• Bit 2 - TOIE1: Timer/Counter1 Overflow Interrupt Enable
When the TOIE1 bit is set (one) and the I-bit in the Status Register is set (one), the
Timer/Counter1 Overflow interrupt is enabled. The corresponding interrupt (at vector $004) is
executed if an overflow in Timer/Counter1 occurs. The Overflow Flag (Timer1) is set (one) in the
Timer/Counter Interrupt Flag Register - TIFR.
• Bit 0 - Res: Reserved Bit
This bit is a reserved bit in the ATtiny25/45/85 and always reads as zero.
• Bit 7 - Res: Reserved Bit
This bit is a reserved bit in the ATtiny25/45/85 and always reads as zero.
• Bit 6 - OCF1A: Output Compare Flag 1A
The OCF1A bit is set (one) when compare match occurs between Timer/Counter1 and the data
value in OCR1A - Output Compare Register 1A. OCF1A is cleared by hardware when executing
the corresponding interrupt handling vector. Alternatively, OCF1A is cleared, after synchroniza-
tion clock cycle, by writing a logic one to the flag. When the I-bit in SREG, OCIE1A, and OCF1A
are set (one), the Timer/Counter1 A compare match interrupt is executed.
• Bit 5 - OCF1B: Output Compare Flag 1B
The OCF1B bit is set (one) when compare match occurs between Timer/Counter1 and the data
value in OCR1B - Output Compare Register 1A. OCF1B is cleared by hardware when executing
the corresponding interrupt handling vector. Alternatively, OCF1B is cleared, after synchroniza-
tion clock cycle, by writing a logic one to the flag. When the I-bit in SREG, OCIE1B, and OCF1B
are set (one), the Timer/Counter1 B compare match interrupt is executed.
• Bit 2 - TOV1: Timer/Counter1 Overflow Flag
In normal mode (PWM1A=0 and PWM1B=0) the bit TOV1 is set (one) when an overflow occurs
in Timer/Counter1. The bit TOV1 is cleared by hardware when executing the corresponding
interrupt handling vector. Alternatively, TOV1 is cleared, after synchronization clock cycle, by
writing a logical one to the flag.
In PWM mode (either PWM1A=1 or PWM1B=1) the bit TOV1 is set (one) when compare match
occurs between Timer/Counter1 and data value in OCR1C - Output Compare Register 1C.
When the SREG I-bit, and TOIE1 (Timer/Counter1 Overflow Interrupt Enable), and TOV1 are set
(one), the Timer/Counter1 Overflow interrupt is executed.
• Bit 0 - Res: Reserved Bit
This bit is a reserved bit in the ATtiny25/45/85 and always reads as zero.
Bit
0x38
Read/Write
Initial value
R
7
0
-
OCF1A
R/W
6
0
OCF1B
R/W
5
0
OCF0A
R/W
4
0
OCF0B
R/W
3
0
TOV1
R/W
2
0
TOV0
R/W
1
0
2586K–AVR–01/08
R
0
0
-
TIFR