ATtiny26 Atmel Corporation, ATtiny26 Datasheet - Page 68

• Manufacturer Part Number: ATtiny26
• Manufacturer: Atmel Corporation

Specifications of ATtiny26

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 11
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 11
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 3
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

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ATtiny26(L)
Figure 39. Timer/Counter1 Synchronization Register Block Diagram
Timer/Counter1 and the prescaler allow running the CPU from any clock source while the pres-
caler is operating on the fast 64 MHz PCK clock in the asynchronous mode.
Note that the system clock frequency must be lower than one half of the PCK frequency. Only
when the system clock is generated from PCK dividing that by two, the ratio of the PCK/system
clock can be exactly two. The synchronization mechanism of the asynchronous Timer/Counter1
needs at least two edges of the PCK when the system clock is high. If the frequency of the sys-
tem clock is too high, it is a risk that data or control values are lost.
The following Figure 40 shows the block diagram for Timer/Counter1.
CK
PCK
PCKE
SYNC
MODE
ASYNC
MODE
IO-registers
OCR1A
OCR1B
OCR1C
TCCR1A
TCCR1B
TCNT1
OCF1A
OCF1B
TOV1
1/2PCK -1CK delay
Input syncronization
registers
1CK delay
S
A
OCR1A_SI
OCR1B_SI
OCR1C_SI
TCCR1A_SI
TCCR1B_SI
TCNT1_SI
OCF1A_SI
OCF1B_SI
TOV1_SI
1PCK delay
8-BIT DATABUS
S
A
Timer/Counter1
TCNT1
1/2PCK -1CK delay
Output
syncronization
registers
TCNT_SO
OCF1A_SO
OCF1B_SO
TOV1_SO
no delay
no delay
Output
multiplexers
S
A
S
A
S
A
S
A
TCNT1
OCF1A
OCF1B
TOV1
1477K–AVR–08/10