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Chapter 38 reload timer, Overview, Features – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 38 Reload Timer

1.Overview

Chapter 38 Reload Timer

1. Overview

The reload timer uses a 16 bit down counter to detect the input signal trigger and perform a count down.

The count length is 16 bits.

2. Features

Operation: 2 kinds of operation are possible

Format: 16 bit down counter with reload register

Quantity: 8 (Output: 8 channels TOT[0-7])

Clock mode: Select from two modes

• Internal clock mode

Count clock: CLKP/2, CLKP/8, CLKP/32, CLKP/64, CLKP/128

Activation triggers (4 types)

• External event clock mode

Count clock

: External event (TIN[7:0] pins)

Count active edge: Rising/falling/both edges of external event

Activation trigger: Software trigger

Cycle

: Cycle = count clock x (reload value + 1)

(Example) When count clock = 16MHz, reload value = 15999

Cycle = 62.5ns x (15999+1) = 1.0ms

Count active edge: When in external event mode, choose from 3 types.

• External trigger (rising /falling/both edges)

Interrupt: Request generated by underflow

Other 1: Counter stop in software/can be reopened

Other 2: Control of other peripheral functions possible

• PPG activation trigger source:

Reload timer 0

:

PPG0, PPG1

Reload timer 1

:

PPG2, PPG3

or

PPG
A/D

Reload value

Down counter

Pin

Latch

Output value

Reversal

Underflow

Reload

Internal clock

or

External event

To PPG
To A/D

Soft trigger

External event

• One-shot Operation

Initial output level

Reversed output level

• Reload Operation

Initial output level

Reversed output level