Rainbow Electronics ATtiny28L - Manual (Page 23)

23
ATtiny28L/V
1062E–10/01
Timer/Counter0
The ATtiny28 provides one general-purpose 8-bit Timer/Counter – Timer/Counter0.
Timer/Counter0 has prescaling selection from the 10-bit prescaling timer. The
Timer/Counter0 can either be used as a timer with an internal clock time base or as a
counter with an external pin connection that triggers the counting.
Timer/Counter Prescaler Figure 20 shows the Timer/Counter prescaler.
Figure 20. Timer/Counter0 Prescaler
The four different prescaled selections are: the hardware modulator period, CK/64,
CK/256 and CK/1028, where CK is the oscillator clock. CK, external source and stop
can also be selected as clock sources.
Figure 21 shows the block diagram for Timer/Counter0.
Figure 21. Timer/Counter0 Block Diagram
10-BIT T/C PRESCALER
0
TIMER/COUNTER0 CLOCK SOURCE
TCK0
CK
T0
CS00
CS01
CS02
CK/256
CK/1024
CK/64
COUNT ENABLE
FROM MODULATOR
T/C0 OVER-
FLOW IRQ
INTERRUPT FLAG
REGISTER (IFR)
T/C0 CONTROL
REGISTER (TCCR0)
TIMER/COUNTER0
(TCNT0)
CONTROL
LOGIC
TO
V
0
INTERRUPT CONTROL
REGISTER (ICR)
T
O
IE0
TO
V
0
T0