
139
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
temporary High Byte Register (TEMP). This temporary register is shared by all the other 16-bit
16.12.11 ICR3H and ICR3L – Input Capture Register 3
The Input Capture is updated with the counter (TCNT3) value each time an event occurs on the
can be used for defining the counter TOP value.
The Input Capture Register is 16-bit in size. To ensure that both the high and low bytes are read
simultaneously when the CPU accesses these registers, the access is performed using an 8-bit
temporary High Byte Register (TEMP). This temporary register is shared by all the other 16-bit
16.12.12 TIMSK1 – Timer/Counter1 Interrupt Mask Register
Bit 7:6 – Reserved
These bits are unused and will always read as zero.
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 globally
enabled), the Timer/Counter1 Input Capture interrupt is enabled. The corresponding Interrupt
Bit 4:3 – Reserved
These bits are unused and will always read as zero.
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 globally
enabled), the Timer/Counter1 Output Compare B Match interrupt is enabled. The corresponding
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 globally
enabled), the Timer/Counter1 Output Compare A Match interrupt is enabled. The corresponding
TIFR1, is set.
Bit
76543210
(0x97)
ICR3[15:8]
ICR3H
(0x96)
ICR3[7:0]
ICR3L
Read/Write
R/W
Initial Value
00000000
Bit
7
65
43
2
1
0
–
–ICIE1
–
OCIE1B
OCIE1A
TOIE1
TIMSK1
Read/Write
R
R/W
R
R/W
Initial Value
0