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FUJITSU F2MCTM-16LX User Manual

Page 273

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CHAPTER 14 16-BIT RELOAD TIMER

[External trigger mode (MOD2 to MOD0="001

B

", "010

B

", "011

B

")]

When the external trigger mode is set, the 16-bit reload timer is started by inputting the external valid edge

to the TIN pin. When the 16-bit reload timer is started, the value set in the 16-bit reload register (TMRLR)

is reloaded to the 16-bit timer register (TMR), starting the TMR count operation.

By setting the operating mode select bits in the timer control status register (TMCSR:MOD2 to MOD0),

the detected edge can be selected from the rising edge, falling edge, and both edges.

Note:

The trigger pulse width of the edge to be inputted to the TIN pin should be 2 T (T: machine cycles) or
more.

Figure 14.5-6 Count Operation in External Trigger Mode (One-shot Mode)

Figure 14.5-7 Count Operation in External Trigger Mode (Reload Mode)

Reload data

0000

H

-1

FFFF

H

Reload data

0000

H

-1

FFFF

H

2T to 2.5T

*

Counter clock

Counter

Data load signal

UF bit

CNTE bit

TIN pin

TOT pin

T: Machine cycle
* : It takes 2T to 2.5T time to load data of reload register from external trigger input.

Start trigger input wait

Reload data

0000

H

Reload data

0000

H

Reload data

0000

H

Reload data

2T to 2.5T

*

-1

-1

-1

-1

Counter clock

Counter

Data load signal

UF bit

CNTE bit

TIN pin

TOT pin

T : Machine cycle
* : It takes 2T to 2.5T time to load data of reload register from external trigger input.