ATMEGA48V_11 ATMEL [ATMEL Corporation], ATMEGA48V_11 Datasheet - Page 136

• Manufacturer Part Number: ATMEGA48V_11
• Description: 8-bit Atmel Microcontroller with 4/8/16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

16.11.9
2545T–AVR–05/11
TIFR1 – Timer/Counter1 interrupt flag register
• Bit 7, 6 – Res: Reserved bits
These bits are unused bits in the Atmel ATmega48/88/168, and will always read as zero.
• Bit 5 – ICF1: Timer/Counter1, input capture flag
This flag is set when a capture event occurs on the ICP1 pin. When the Input Capture Register
(ICR1) is set by the WGM13:0 to be used as the TOP value, the ICF1 Flag is set when the coun-
ter reaches the TOP value.
ICF1 is automatically cleared when the Input Capture Interrupt Vector is executed. Alternatively,
ICF1 can be cleared by writing a logic one to its bit location.
• Bit 4, 3 – Res: Reserved bits
These bits are unused bits in the ATmega48/88/168, and will always read as zero.
• Bit 2 – OCF1B: Timer/Counter1, output compare B match flag
This flag is set in the timer clock cycle after the counter (TCNT1) value matches the Output
Compare Register B (OCR1B).
Note that a Forced Output Compare (FOC1B) strobe will not set the OCF1B Flag.
OCF1B is automatically cleared when the Output Compare Match B Interrupt Vector is exe-
cuted. Alternatively, OCF1B can be cleared by writing a logic one to its bit location.
• Bit 1 – OCF1A: Timer/Counter1, output compare A match flag
This flag is set in the timer clock cycle after the counter (TCNT1) value matches the Output
Compare Register A (OCR1A).
Note that a Forced Output Compare (FOC1A) strobe will not set the OCF1A Flag.
OCF1A is automatically cleared when the Output Compare Match A Interrupt Vector is exe-
cuted. Alternatively, OCF1A can be cleared by writing a logic one to its bit location.
• Bit 0 – TOV1: Timer/Counter1, overflow flag
The setting of this flag is dependent of the WGM13:0 bits setting. In Normal and CTC modes,
the TOV1 Flag is set when the timer overflows. Refer to
Flag behavior when using another WGM13:0 bit setting.
TOV1 is automatically cleared when the Timer/Counter1 Overflow Interrupt Vector is executed.
Alternatively, TOV1 can be cleared by writing a logic one to its bit location.
Bit
0x16 (0x36)
Read/write
Initial value
R
7
–
0
R
6
–
0
ICF1
R/W
5
0
R
4
–
0
R
3
–
0
Table 16-4 on page 132
OCF1B
R/W
ATmega48/88/168
2
0
OCF1A
R/W
1
0
TOV1
R/W
0
0
for the TOV1
TIFR1
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