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Chapter 7 Timer/Counter Units
7
7.3 8-BIT TIMER/COUNTER 27.3.1 Functions

Eight-bit timer/counter 2 has two functions not available with the other three timers/counters:

External event counter

One-shot timer

This section describes the following four basic functions in sequence:

Interval timer

Programmable square wave output

Pulse width measurement

External event counter

(1) Interval timer

When operating as an interval timer, 8-bit timer/counter 2 generates an internal interrupt at specified intervals.

Table 7-11 Intervals of 8-Bit Timer/Counter 2

Resolution
16/fCLK
(2.6
µ
s)
32/fCLK
(5.3
µ
s)
64/fCLK
(10.7
µ
s)
128/fCLK
(21.3
µ
s)
256/fCLK
(42.7
µ
s)
512/fCLK
(85.3
µ
s)
Maximum interval
28 × 16/fCLK
(683
µ
s)
28 × 32/fCLK
(1.37 ms)
28 × 64/fCLK
(2.73 ms)
28 × 128/fCLK
(5.46 ms)
28 × 256/fCLK
(10.9 ms)
28 × 512/fCLK
(21.8 ms)
Minimum interval
16/fCLK
(2.6
µ
s)
32/fCLK
(5.3
µ
s)
64/fCLK
(10.7
µ
s)
128/fCLK
(21.3
µ
s)
256/fCLK
(42.7
µ
s)
512/fCLK
(85.3
µ
s)
The values in parentheses are based on fCLK = 6 MHz.