ATtiny88 Atmel Corporation, ATtiny88 Datasheet - Page 95

• Manufacturer Part Number: ATtiny88
• Manufacturer: Atmel Corporation

Specifications of ATtiny88

• Flash (kbytes): 8 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 12 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 12
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 28
• Ext Interrupts: 28
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 64
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 4
• Input Capture Channels: 1
• Pwm Channels: 2
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

12.6
8008H–AVR–04/11
Input Capture Unit
are generated on the Output Compare outputs OC1x. For more details about advanced counting
sequences and waveform generation, see
The Timer/Counter Overflow Flag (TOV1) is set according to the mode of operation selected by
the WGM1[3:0] bits. TOV1 can be used for generating a CPU interrupt.
The Timer/Counter incorporates an Input Capture unit that can capture external events and give
them a time-stamp indicating time of occurrence. The external signal indicating an event, or mul-
tiple events, can be applied via the ICP1 pin or alternatively, via the analog-comparator unit. The
time-stamps can then be used to calculate frequency, duty-cycle, and other features of the sig-
nal applied. Alternatively the time-stamps can be used for creating a log of the events.
The Input Capture unit is illustrated by the block diagram shown in
the block diagram that are not directly a part of the Input Capture unit are gray shaded. The
small “n” in register and bit names indicates the Timer/Counter number.
Figure 12-3. Input Capture Unit Block Diagram
When a change of the logic level (an event) occurs on the Input Capture pin (ICP1), alternatively
on the Analog Comparator output (ACO), and this change confirms to the setting of the edge
detector, a capture will be triggered. When a capture is triggered, the 16-bit value of the counter
(TCNT1) is written to the Input Capture Register (ICR1). The Input Capture Flag (ICF1) is set at
the same system clock as the TCNT1 value is copied into ICR1 Register. If enabled (ICIE1 = 1),
the Input Capture Flag generates an Input Capture interrupt. The ICF1 Flag is automatically
cleared when the interrupt is executed. Alternatively the ICF1 Flag can be cleared by software
by writing a logical one to its I/O bit location.
ICPn
WRITE
ICRnH (8-bit)
TEMP (8-bit)
Comparator
Analog
ICRn (16-bit Register)
ACO*
ICRnL (8-bit)
ACIC*
DATA BUS
“Modes of Operation” on page
Canceler
ICNC
Noise
(8-bit)
TCNTnH (8-bit)
TCNTn (16-bit Counter)
Detector
ICES
Edge
Figure
ATtiny48/88
100.
12-3. The elements of
TCNTnL (8-bit)
ICFn (Int.Req.)
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