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Timsk1 - timer/counter1 interrupt mask register, Tifr1 - timer/counter1 interrupt flag register – Rainbow Electronics ATmega3290P_V User Manual

Page 131

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131

ATmega329/3290/649/6490

2552H–AVR–11/06

TIMSK1 – Timer/Counter1
Interrupt Mask Register

• Bit 5 – ICIE1: Timer/Counter1, Input Capture Interrupt Enable

When this bit is written to one, and the I-flag in the Status Register is set (interrupts glo-
bally enabled), the Timer/Counter1 Input Capture interrupt is enabled. The
corresponding Interrupt Vector (See “Interrupts” on page 49.) is executed when the
ICF1 Flag, located in TIFR1, is set.

• Bit 2 – 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 glo-
bally enabled), the Timer/Counter1 Output Compare B Match interrupt is enabled. The
corresponding Interrupt Vector (See “Interrupts” on page 49.) is executed when the
OCF1B Flag, located in TIFR1, is set.

• Bit 1 – 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 glo-
bally enabled), the Timer/Counter1 Output Compare A Match interrupt is enabled. The
corresponding Interrupt Vector (See “Interrupts” on page 49.) is executed when the
OCF1A Flag, located in TIFR1, is set.

• Bit 0 – TOIE1: Timer/Counter1, Overflow Interrupt Enable

When this bit is written to one, and the I-flag in the Status Register is set (interrupts glo-
bally enabled), the Timer/Counter1 Overflow interrupt is enabled. The corresponding
Interrupt Vector (See “Interrupts” on page 49.) is executed when the TOV1 Flag, located
in TIFR1, is set.

TIFR1 – Timer/Counter1
Interrupt Flag Register

• 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. Alter-
natively, ICF1 can be cleared by writing a logic one to its bit location.

• 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 Out-
put 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
executed. Alternatively, OCF1B can be cleared by writing a logic one to its bit location.

Bit

7

6

5

4

3

2

1

0

(0x6F)

ICIE1

OCIE1B

OCIE1A

TOIE1

TIMSK1

Read/Write

R

R

R/W

R

R

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

0x16 (0x36)

ICF1

OCF1B

OCF1A

TOV1

TIFR1

Read/Write

R

R

R/W

R

R

R/W

R/W

R/W

Initial Value

0

0

0

0

0

0

0

0