attiny25v ATMEL Corporation, attiny25v Datasheet - Page 70

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

11.4
70
Counter Unit
ATtiny25/45/85
Figure 11-3. Timer/Counter0 Prescaler
The synchronization logic on the input pins (T0) in
69.
The main part of the 8-bit Timer/Counter is the programmable bi-directional counter unit.
11-4
Figure 11-4. Counter Unit Block Diagram
Signal description (internal signals):
PSR10
clk
shows a block diagram of the counter and its surroundings.
count
direction
clear
clk
top
bottom
T0
I/O
Tn
DATA BUS
Synchronization
TCNTn
Increment or decrement TCNT0 by 1.
Select between increment and decrement.
Clear TCNT0 (set all bits to zero).
Timer/Counter clock, referred to as clk
Signalize that TCNT0 has reached maximum value.
Signalize that TCNT0 has reached minimum value (zero).
Clear
direction
count
clear
bottom
Control Logic
Figure 11-3
top
TOVn
(Int.Req.)
clk
Tn
is shown in
Clock Select
clk
( From Prescaler )
T0
Detector
Edge
T0
in the following.
Figure 11-2 on page
2586K–AVR–01/08
Figure
Tn