Datasheet

97
ATmega8A [DATASHEET]
8159E–AVR–02/2013
(TEMP). This temporary register is shared by all the other 16-bit registers. See “Accessing 16-bit Registers” on
page 75.
17.11.7 TIMSK
(1)
– Timer/Counter Interrupt Mask Register
Note: 1. This register contains interrupt control bits for several Timer/Counters, but only Timer1 bits are described in this
section. The remaining bits are described in their respective timer sections.
• Bit 5 – TICIE1: Timer/Counter1, Input Capture Interrupt Enable
When this bit is written to one, and the I-flag in the Status Register is set (interrupts globally enabled), the
Timer/Counter1 Input Capture Interrupt is enabled. The corresponding Interrupt Vector (see “Interrupts” on page
44) is executed when the ICF1 Flag, located in TIFR, is set.
• Bit 4 – OCIE1A: Timer/Counter1, Output Compare A Match Interrupt Enable
When this bit is written to one, and the I-flag in the Status Register is set (interrupts globally enabled), the
Timer/Counter1 Output Compare A match interrupt is enabled. The corresponding Interrupt Vector (see “Inter-
rupts” on page 44) is executed when the OCF1A Flag, located in TIFR, is set.
• Bit 3 – OCIE1B: Timer/Counter1, Output Compare B Match Interrupt Enable
When this bit is written to one, and the I-flag in the Status Register is set (interrupts globally enabled), the
Timer/Counter1 Output Compare B match interrupt is enabled. The corresponding Interrupt Vector (see “Inter-
rupts” on page 44) is executed when the OCF1B Flag, located in TIFR, is set.
• Bit 2 – TOIE1: Timer/Counter1, Overflow Interrupt Enable
When this bit is written to one, and the I-flag in the Status Register is set (interrupts globally enabled), the
Timer/Counter1 Overflow Interrupt is enabled. The corresponding Interrupt Vector (see “Interrupts” on page 44) is
executed when the TOV1 Flag, located in TIFR, is set.
17.11.8 TIFR
(1)
– Timer/Counter Interrupt Flag Register
Note: 1. This register contains flag bits for several Timer/Counters, but only Timer1 bits are described in this section. The
remaining bits are described in their respective timer sections.
• 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 counter 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 – 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.
Bit 76543210
OCIE2 TOIE2 TICIE1 OCIE1A OCIE1B TOIE1
–
TOIE0 TIMSK
Read/Write R/W R/W R/W R/W R/W R/W R R/W
Initial Value00000000
Bit 76543210
OCF2 TOV2 ICF1 OCF1A OCF1B TOV1 – TOV0 TIFR
Read/Write R/W R/W R/W R/W R/W R/W R R/W
Initial Value00000000