ATMEGA325 Datasheet, PDF (134/347 Pages) ATMEL Corporation – 8-bit Microcontroller with In-System Programmable Flash

Figure 62. Timer/Counter Timing Diagram, Setting of OCF2A, with Prescaler (f_{clk_I/O}/8)
clk_I/O
clk_Tn
(clk_I/O/8)
TCNTn
OCRnx - 1
OCRnx
OCRnx + 1
OCRnx + 2
OCRnx
OCRnx Value
OCFnx
Figure 63 shows the setting of OCF2A and the clearing of TCNT2 in CTC mode.
Figure 63. Timer/Counter Timing Diagram, Clear Timer on Compare Match mode, with
Prescaler (f_{clk_I/O}/8)
clk_I/O
clk_Tn
(clk_I/O/8)
TCNTn
(CTC)
OCRnx
TOP - 1
TOP
BOTTOM
TOP
BOTTOM + 1
OCFnx
134 ATmega325/3250/645/6450
2570A–AVR–09/04