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3 8-bit timer/counter 2, 1 functions, Chapter 7 timer/counter units – NEC PD78214 User Manual

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Chapter 7 Timer/Counter Units

7

7.3 8-BIT TIMER/COUNTER 2

7.3.1 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/f

CLK

(2.6

µs)

32/f

CLK

(5.3

µs)

64/f

CLK

(10.7

µs)

128/f

CLK

(21.3

µs)

256/f

CLK

(42.7

µs)

512/f

CLK

(85.3

µs)

Maximum interval

2

8

× 16/f

CLK

(683

µs)

2

8

× 32/f

CLK

(1.37 ms)

2

8

× 64/f

CLK

(2.73 ms)

2

8

× 128/f

CLK

(5.46 ms)

2

8

× 256/f

CLK

(10.9 ms)

2

8

× 512/f

CLK

(21.8 ms)

Minimum interval

16/f

CLK

(2.6

µs)

32/f

CLK

(5.3

µs)

64/f

CLK

(10.7

µs)

128/f

CLK

(21.3

µs)

256/f

CLK

(42.7

µs)

512/f

CLK

(85.3

µs)

The values in parentheses are based on f

CLK

= 6 MHz.

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