Datasheet

19.7.1 TCCR0 – Timer/Counter Control Register
Name: TCCR0
Offset: 0x33 [ID-000004b0]
Reset: 0
Property: When addressing I/O Registers as data space the offset address is 0x53
When using the I/O specific commands IN and OUT, the I/O addresses 0x00 - 0x3F must be used. When
addressing I/O Registers as data space using LD and ST instructions, 0x20 must be added to these offset
addresses.
Bit 7 6 5 4 3 2 1 0
CS0n[2:0]
Access
R/W R/W R/W
Reset 0 0 0
Bits 2:0 – CS0n[2:0] Clock Select [n = 2:0]
The three clock select bits select the clock source to be used by the Timer/Counter.
CS02 CS01 CS00 Description
0 0 0 No clock source (Timer/Counter stopped).
0 0 1 clk
I/O
/(No prescaling)
0 1 0 clk
I/O
/8 (From prescaler)
0 1 1 clk
I/O
/64 (From prescaler)
1 0 0 clk
I/O
/256 (From prescaler)
1 0 1 clk
I/O
/1024 (From prescaler)
1 1 0 External clock source on T0 pin. Clock on falling edge.
1 1 1 External clock source on T0 pin. Clock on rising edge.
If external pin modes are used for the Timer/Counter0, transitions on the T0 pin will clock the counter
even if the pin is configured as an output. This feature allows software control of the counting.
AVR 8-Bit Microcontroller
8-bit Timer/Counter0
© 2017 Microchip Technology Inc.
Datasheet Complete
40001974A-page 107