ATtiny261 Atmel Corporation, ATtiny261 Datasheet - Page 114

• Manufacturer Part Number: ATtiny261
• Manufacturer: Atmel Corporation

Specifications of ATtiny261

• Flash (kbytes): 2 Kbytes
• Pin Count: 20
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 16
• Ext Interrupts: 16
• 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: Yes
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• 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: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

114
ATtiny261/461/861
• Bits 5,4 – COM1B1, COM1B0: Comparator B Output Mode, Bits 1 and 0
These bits control the behaviour of the Waveform Output (OCW1B) and the connection of the
Output Compare pin (OC1B). If one or both of the COM1B1:0 bits are set, the OC1B output
overrides the normal port functionality of the I/O pin it is connected to. The complementary
OC1B output is connected only in PWM modes when the COM1B1:0 bits are set to “01”. Note
that the Data Direction Register (DDR) bit corresponding to the OC1B pin must be set in order to
enable the output driver.
The function of the COM1B1:0 bits depends on the PWM1B and WGM11:10 bit settings.
12-13
PWM).
Table 12-13. Compare Output Mode, Normal Mode (non-PWM)
Table 12-14
set to Fast PWM Mode.
Table 12-14. Compare Output Mode, Fast PWM Mode
Table 12-15
set to Phase and Frequency Correct PWM Mode.
Table 12-15. Compare Output Mode, Phase and Frequency Correct PWM Mode
Bits COM1B1 and COM1B0 are shadowed in TCCR1C. Writing to bits COM1B1 and COM1B0
will also change bits COM1B1S and COM1B0S in TCCR1C. Similary, changes written to bits
COM1B1:0
COM1B1:0
COM1B1:0
00
01
10
00
01
10
00
01
10
11
11
11
shows the COM1B1:0 bit functionality when the PWM1B bit is set to Normal Mode (non-
shows the COM1B1:0 bit functionality when the PWM1B and WGM11:10 bits are
shows the COM1B1:0 bit functionality when the PWM1B and WGM11:10 bits are
OCW1B Behaviour
Normal port operation.
Toggle on Compare Match.
Clear on Compare Match.
Set on Compare Match.
OCW1B Behaviour
Normal port operation.
Cleared on Compare Match.
Set when TCNT1 = 0x000.
Cleared on Compare Match.
Set when TCNT1 = 0x000.
Set on Compare Match.
Cleared when TCNT1 = 0x000.
OCW1B Behaviour
Normal port operation.
Cleared on Compare Match when up-counting.
Set on Compare Match when down-counting.
Cleared on Compare Match when up-counting.
Set on Compare Match when down-counting.
Set on Compare Match when up-counting.
Cleared on Compare Match when down-counting.
OC1B Pin
Connected
Connected
Connected
OC1B Pin
Disconnected
Connected
Connected
Connected
Disconnected
OC1B Pin
Disconnected
Connected
Connected
Connected
OC1B Pin
Disconnected
Connected
Disconnected
Disconnected
OC1B Pin
Disconnected
Disconnected
Disconnected
Disconnected
OC1B Pin
Disconnected
Connected
Disconnected
Disconnected
2588E–AVR–08/10
Table