Datasheet

ManualsBrandsMICROCHIP TECHNOLOGY ManualsMicrocontrollers, Microprocessors & QuartzesEmbedded microcontroller SOT 23 8-Bit 12 MHz I/O number 4

ATtiny4/5/9/10 [DATASHEET]

8127F–AVR–02/2013

ported by the Timer/Counter unit are: Normal mode (counter), Clear Timer on Compare match (CTC) mode, and

three types of Pulse Width Modulation (PWM) modes. (“Modes of Operation” on page 61).

11.11.2 TCCR0B – Timer/Counter0 Control Register B

• Bit 7 – ICNC0: Input Capture Noise Canceler

Setting this bit (to one) activates the Input Capture Noise Canceler. When the noise canceler is activated, the input

from the Input Capture pin (ICP0) is filtered. The filter function requires four successive equal valued samples of

the ICP0 pin for changing its output. The Input Capture is therefore delayed by four oscillator cycles when the noise

canceler is enabled.

• Bit 6 – ICES0: Input Capture Edge Select

This bit selects which edge on the Input Capture pin (ICP0) that is used to trigger a capture event. When the ICES0

bit is written to zero, a falling (negative) edge is used as trigger, and when the ICES0 bit is written to one, a rising

(positive) edge will trigger the capture.

When a capture is triggered according to the ICES0 setting, the counter value is copied into the Input Capture Reg-

ister (ICR0). The event will also set the Input Capture Flag (ICF0), and this can be used to cause an Input Capture

Interrupt, if this interrupt is enabled.

Table 11-5. Waveform Generation Modes

Mode

WGM

3:0 Mode of Operation TOP

Update of

OCR0x at

TOV0 Flag

Set on

0 0000 Normal 0xFFFF Immediate MAX

1 0001 PWM, Phase Correct, 8-bit 0x00FF TOP BOTTOM

2 0010 PWM, Phase Correct, 9-bit 0x01FF TOP BOTTOM

3 0011 PWM, Phase Correct, 10-bit 0x03FF TOP BOTTOM

40100CTC (

Clear Timer on Compare) OCR0A Immediate MAX

5 0101 Fast PWM, 8-bit 0x00FF TOP TOP

6 0110 Fast PWM, 9-bit 0x01FF TOP TOP

7 0111 Fast PWM, 10-bit 0x03FF TOP TOP

8 1000 PWM, Phase & Freq. Correct ICR0 BOTTOM BOTTOM

9 1001 PWM, Phase & Freq. Correct OCR0A BOTTOM BOTTOM

10 1010 PWM, Phase Correct ICR0 TOP BOTTOM

11 1011 PWM, Phase Correct OCR0A TOP BOTTOM

12 1100 CTC (

Clear Timer on Compare) ICR0 Immediate MAX

13 1101 (Reserved) – – –

14 1110 Fast PWM ICR0 TOP TOP

15 1111 Fast PWM OCR0A TOP TOP

Bit 7654 3210

0x2D ICNC0 ICES0

– WGM03 WGM02 CS02 CS01 CS00 TCCR0B

Read/Write R/W R/W R R/W R/W R/W R/W R/W

Initial Value 0 0 0 0 0 0 0 0