ATtiny48 Atmel Corporation, ATtiny48 Datasheet - Page 54

• Manufacturer Part Number: ATtiny48
• Manufacturer: Atmel Corporation

Specifications of ATtiny48

• Flash (kbytes): 4 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): 0.25
• 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

9.2.1
9.2.2
54
ATtiny48/88
Pin Change Interrupt Timing
Low Level Interrupt
means that these interrupts can be used for waking the part also from sleep modes other than
Idle mode.
The INT0 and INT1 interrupts can be triggered by a falling or rising edge, or a low level. This is
configured as described in
INT0 or INT1 interrupts are enabled and are configured as level triggered, the interrupts will trig-
ger as long as the corresponding pin is held low. Note that recognition of falling or rising edge
interrupts on INT0 or INT1 requires the presence of an I/O clock, described in
clkI/O” on page
An example of timing of a pin change interrupt is shown in
Figure 9-1.
Low level interrupts on INT0 and INT1 are detected asynchronously. This means that the inter-
rupt sources can be used for waking the part also from sleep modes other than Idle (the I/O
clock is halted in all sleep modes except Idle mode).
Note that if a level triggered interrupt is used for wake-up from Power-down, the required level
must be held long enough for the MCU to complete the wake-up to trigger the level interrupt. If
the level disappears before the end of the Start-up Time, the MCU will still wake up, but no inter-
pcint_setflag
pcint_in_(0)
PCINT(0)
pcint_syn
pin_sync
pin_lat
PCINT(0)
PCIF
clk
clk
Timing of pin change interrupts
28.
LE
pin_lat
D
“EICRA – External Interrupt Control Register A” on page
Q
pin_sync
PCINT(0) in PCMSK(x)
pcint_in_(0)
0
x
clk
Figure
9-1.
pcint_syn
pcint_setflag
8008H–AVR–04/11
“I/O Clock –
55. When
PCIF