ATtiny85 Atmel Corporation, ATtiny85 Datasheet - Page 80

• Manufacturer Part Number: ATtiny85
• Manufacturer: Atmel Corporation

Specifications of ATtiny85

• Flash (kbytes): 8 Kbytes
• Pin Count: 8
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 3
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 6
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• 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): 512
• 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: 5
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

11.9
11.9.1
11.9.2
80
Register Description
ATtiny25/45/85
GTCCR – General Timer/Counter Control Register
TCCR0A – Timer/Counter Control Register A
• Bit 7 – TSM: Timer/Counter Synchronization Mode
Writing the TSM bit to one activates the Timer/Counter Synchronization Mode. In this mode, the
value written to PSR0 is kept, hence keeping the Prescaler Reset signal asserted. This ensures
that the timer/counter is halted and can be configured without the risk of advancing during con-
figuration. When the TSM bit is written to zero, the PSR0 bit is cleared by hardware, and the
timer/counter start counting.
• Bit 0 – PSR0: Prescaler Reset Timer/Counter0
When this bit is one, the Timer/Counter0 prescaler will be Reset. This bit is normally cleared
immediately by hardware, except if the TSM bit is set.
• Bits 7:6 – COM0A[1:0]: Compare Match Output A Mode
• Bits 5:4 – COM0B[1:0]: Compare Match Output B Mode
The COM0A[1:0] and COM0B[1:0] bits control the behaviour of Output Compare pins OC0A and
OC0B, respectively. If any of the COM0A[1:0] bits are set, the OC0A output overrides the normal
port functionality of the I/O pin it is connected to. Similarly, if any of the COM0B[1:0] bits are set,
the OC0B output overrides the normal port functionality of the I/O pin it is connected to. How-
ever, note that the Data Direction Register (DDR) bit corresponding to the OC0A and OC0B pins
must be set in order to enable the output driver.
When OC0A/OC0B is connected to the I/O pin, the function of the COM0A[1:0]/COM0B[1:0] bits
depend on the WGM0[2:0] bit setting.
the WGM0[2:0] bits are set to a normal or CTC mode (non-PWM).
Table 11-2.
Bit
0x2C
Read/Write
Initial Value
Bit
0x2A
Read/Write
Initial Value
COM0A1
COM0B1
0
0
1
1
COM0A1
Compare Output Mode, non-PWM Mode
TSM
R/W
R/W
7
0
7
0
COM0A0
COM0B0
0
1
0
1
PWM1B
COM0A0
R/W
R
6
0
6
0
Description
Normal port operation, OC0A/OC0B disconnected.
Toggle OC0A/OC0B on Compare Match
Clear OC0A/OC0B on Compare Match
Set OC0A/OC0B on Compare Match
COM1B1
COM0B1
R/W
R
5
0
5
0
Table 11-2
COM0B0
COM1B0
R/W
4
0
R
4
0
shows the COM0x[1:0] bit functionality when
FOC1B
R
3
–
0
R
3
0
FOC1A
R
2
–
0
R
2
0
WGM01
R/W
PSR1
1
0
R
1
0
WGM00
R/W
PSR0
R/W
0
0
0
0
2586N–AVR–04/11
TCCR0A
GTCCR