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8 functions of operations of capture functions, Functions of operations of capture functions – FUJITSU F2MC-8L F202RA User Manual

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CHAPTER 8 8/16-BIT CAPTURE TIMER/COUNTER

8.8

Functions of Operations of Capture Functions

This section describes the capture function operation of the 8/16-bit capture timer/
counter.

Capture Function Operation

8-bit mode

To operate the capture function in the 8-bit mode, the function must be set as shown in Figure 8.8-1 .

Figure 8.8-1 Setting of Capture Function in 8-bit Mode

The 8-bit capture mode is allowed by the capture mode enable/edge detection selection bits (EDGS1 and

EDGS0) of the capture control register (TCCR). "1" is written to the timer start bit (TSTR0) after the clock

source selection bits (TCS02, TCS01, and TCS00) of the timer 0 control register (TCR0) have been set.

In the capture mode, the count value is captured to the capture data register (TCPL) each time a capture

input edge is detected and the capture edge detection flag (CPIF) is set to "1". In this case, if the capture

interrupt enable bit (CPIEN) is already set to "1", an interrupt request is output to the CPU.

The capture mode is divided into free-run mode and clear mode.

bit7

bit6

bit5

bit4

bit3

bit2

bit1

bit0

DDR3

0

TCCR

CPIF

CFCLR CPIEN

CCMSK TCMSK EDGS1 EDGS0

RESV

TCR1

TIF1

TFCR1

T1IEN

TCS12

TCS11

TCS10

TSTR1

TCR0

TIF0

TFCR0

T0IEN

CINV

TCS02

TCS01

TCS00

TSTR0

TCR2

PEN

TSEL

TCPL

: Used bit

: Unused bit

0

: Set "0"

Setting of a value
other than 00

Setting of a value other
than 111

Setting of a value other
than 111

Number of detected events

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