8.4
Operation
8.4.1
FRC Increment Timing
FRC increments on a pulse generated once for each period of the selected (internal or external)
clock source. The clock source is selected by bits CKS0 and CKS1 in TCR.
Internal Clock: The internal clock sources (øP/2, øP/8, øP/32) are created from the system clock
(ø) by a prescaler. FRC increments on a pulse generated from the falling edge of the prescaler
output. See figure 8.4.
ø
Internal
clock
FRC clock
pulse
FRC
N – 1
N
N + 1
Figure 8.4 Increment Timing for Internal Clock Source
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