ATMEGA328P-20PU Atmel, ATMEGA328P-20PU Datasheet - Page 136

• Manufacturer Part Number: ATMEGA328P-20PU
• Manufacturer: Atmel

Specifications of ATMEGA328P-20PU

• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SPI/TWI/USART
• Program Memory Type: Flash
• Program Memory Size: 32KB
• Total Internal Ram Size: 2KB
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 6-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Through Hole
• Pin Count: 28
• Package Type: PDIP
• Lead Free Status / Rohs Status: Compliant

15.11.7
15.11.8
8025K–AVR–10/09
ICR1H and ICR1L – Input Capture Register 1
TIMSK1 – Timer/Counter1 Interrupt Mask Register
The Input Capture is updated with the counter (TCNT1) value each time an event occurs on the
ICP1 pin (or optionally on the Analog Comparator output for Timer/Counter1). 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
registers.
• Bit 7, 6 – Res: Reserved Bits
These bits are unused bits in the ATmega48P/88P/168P, 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
Vector (see “Interrupts” on page 57) is executed when the ICF1 Flag, located in TIFR1, is set.
• Bit 4, 3 – Res: Reserved Bits
These bits are unused bits in the ATmega48P/88P/168P, 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
Interrupt Vector (see “Interrupts” on page 57) 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 globally
enabled), the Timer/Counter1 Output Compare A Match interrupt is enabled. The corresponding
Interrupt Vector (see “Interrupts” on page 57) 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 globally
enabled), the Timer/Counter1 Overflow interrupt is enabled. The corresponding Interrupt Vector
(See
Bit
(0x87)
(0x86)
Read/Write
Initial Value
Bit
(0x6F)
Read/Write
Initial Value
”Interrupts” on page
See Section “15.3” on page 112.
R/W
R
7
0
7
–
0
R/W
57) is executed when the TOV1 Flag, located in TIFR1, is set.
R
6
0
6
–
0
ICIE1
R/W
R/W
5
0
5
0
R/W
R
4
–
0
4
0
ICR1[15:8]
ICR1[7:0]
R/W
R
3
–
0
3
0
ATmega48P/88P/168P
OCIE1B
R/W
R/W
2
0
2
0
OCIE1A
R/W
R/W
1
0
1
0
TOIE1
R/W
R/W
0
0
0
0
TIMSK1
ICR1H
ICR1L
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