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¡ Semiconductor

MSM82C54-2RS/GS/JS

• Count value writing during counting:

The count value writing does not affect the current counting sequence. If the gate trigger is

generated after the new count value is written and before the current counting ends, the new

count value is loaded to the CE at the falling edge of the next clock pulse, and counting

continues using the new count value. The various roles of the gate input signals in the above

modes are summarized in the following table.

0

1

"H" Level

"L" Level Falling Edge

Rising Edge

Mode

Gate

Counting not possible

Counting possible

(1)

(2)

Start of counting

Retriggering

2

(1)

(2)

Counting not possible

Counter output forced to "H" level

Start of counting

Counting possible

3

(1)

(2)

Counting not possible

Counter output forced to "H" level

Start of counting

Counting possible

4

Counting not possible

Counting possible

5

(1)

(2)

Start of counting

Retriggering