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Atmega169v/l – Rainbow Electronics Atmega169L User Manual

Page 115

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115

ATmega169V/L

2514A–AVR–08/02

Figure 50. Timer/Counter Timing Diagram, no Prescaling

Figure 51 shows the same timing data, but with the prescaler enabled.

Figure 51. Timer/Counter Timing Diagram, with Prescaler (f

clk_I/O

/8)

TOVn

(FPWM)

and ICFn

(if used

as TOP)

OCRnx

(Update at TOP)

TCNTn

(CTC and FPWM)

TCNTn

(PC and PFC PWM)

TOP - 1

TOP

TOP - 1

TOP - 2

Old OCRnx Value

New OCRnx Value

TOP - 1

TOP

BOTTOM

BOTTOM + 1

clk

Tn

(clk

I/O

/1)

clk

I/O

TOVn

(FPWM)

and ICF n

(if used

as TOP)

OCRnx

(Update at TOP)

TCNTn

(CTC and FPWM)

TCNTn

(PC and PFC PWM)

TOP - 1

TOP

TOP - 1

TOP - 2

Old OCRnx Value

New OCRnx Value

TOP - 1

TOP

BOTTOM

BOTTOM + 1

clk

I/O

clk

Tn

(clk

I/O

/8)