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The timer/counter0 control register – tccr0, Attiny15l, Table 9. clock 0 prescale select – Rainbow Electronics ATtiny15L User Manual

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ATtiny15L

1187E–AVR–06/02

Figure 20. Timer/Counter0 Block Diagram

The Timer/Counter0 Control
Register – TCCR0

• Bits 7..3 – Res: Reserved Bits

These bits are reserved bits in the ATtiny15L and always read as zero.

• Bits 2, 1, 0 – CS02, CS01, CS00: Clock Select0, Bits 2, 1 and 0

The Clock Select0 bits 2, 1 and 0 define the prescaling source of Timer0.

The Stop condition provides a Timer Enable/Disable function. The prescaled CK modes
are scaled directly from the CK Oscillator clock. If the external pin modes are used for
Timer/Counter0, transitions on PB2/(T0) will clock the counter even if the pin is config-
ured as an output. This feature can give the user SW control of counting.

OCIE1A

T

O

IE1

T

O

IE0

TO

V

0

TO

V

0

CS02

CS01

CS00

TO

V

1

OCF1A

T/C CLK SOURCE

Bit

7

6

5

4

3

2

1

0

$33

CS02

CS01

CS00

TCCR0

Read/Write

R

R

R

R

R

R/W

R/W

R/W

Initial Value

0

0

0

0

0

0

0

0

Table 9. Clock 0 Prescale Select

CS02

CS01

CS00

Description

0

0

0

Stop, the Timer/Counter0 is stopped.

0

0

1

CK

0

1

0

CK/8

0

1

1

CK/64

1

0

0

CK/256

1

0

1

CK/1024

1

1

0

External Pin T0, falling edge

1

1

1

External Pin T0, rising edge