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
ICPn pin (or optionally on the Analog Comparator output for Timer/Counter3). The Input Capture
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