Datasheet

CA12 CA11 CS10 Description
1 0 0 clkI/O/256 (From prescaler)
1 0 1 clk
I/O
/1024 (From prescaler)
1 1 0 External clock source on Tn pin. Clock on falling edge.
1 1 1 External clock source on Tn pin. Clock on rising edge.
If external pin modes are used for the Timer/Countern, transitions on the Tn pin will clock the counter
even if the pin is configured as an output. This feature allows software control of the counting.
Atmel ATmega64A [DATASHEET]
Atmel-8160E-ATmega64A_Datasheet_Complete-09/2015
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