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8 operation when returning from stop mode, 9 status transition – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 38 Reload Timer

5.Operation

5.8 Operation when Returning from Stop Mode

When returning due to an external interrupt, the reload timer will continue operation from its stopped state.

When returning from a reset (INITX), it will return to the initial state (down counter stopped, no TOT pin
output).

5.9 Status Transition

The status of the counter is decided by the CNTE bit of the reload timer control register and the internal WAIT
signal.

Settable statuses are:

STOP status: Stopped (CNTE=“0”, WAIT=“1”)

WAIT status: Waiting for activation trigger (CNTE=“1”, WAIT=“1”)

RUN status : Count operation running (CNTE=“1”, WAIT=“0”)

LOAD status: Loading value to counter (from RUN/WAIT, TRG=“1” or underflow: CNTE=“1”, WAIT=“0”)

Figure 5-1 Status Transition Diagram

STOP CNTE=0,WAIT=1

Counter: Retains value

when stopped

Indeterminate after reset

Counter: Retains value

when stopped

Indeterminate until load

after reset

Reset

WAIT

CNTE=1,WAIT=1

RUN

CNTE=1,WAIT=0

Counter: Operation

LOAD CNTE=1,WAIT=0

Load reload register

content to counter

Status Transition from Hardware

Status Transition from Register Access

CNTE="1"

TRG="0"

CNTE="1"
TRG="1"

RELD UF

TRG="1"

TRG="1"

RELD-UF

.

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