M30620FCAFP datasheet(359/615 Pages) RENESAS

359 / 615 page

Timer B

Mitsubishi microcomputers

M16C / 62A Group

SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

2-42

In timer mode, choose functions from those listed in Table 2.3.1. Operations of the circled items are

described below. Figure 2.3.4 shows the operation timing, and Figure 2.3.5 shows the set-up procedure.

2.3.2 Operation of Timer B (timer mode)

Item

Count source

Set-up

Internal count source (f1 / f8 / f32 / fc32)

Operation

Table 2.3.1. Choosed functions

(1) Setting the count start flag to “1” causes the counter to perform a down count on the count

source.

(2) If an underflow occurs, the content of the reload register is reloaded, and the counter contin-

ues counting. At this time, the timer Bi interrupt request bit goes to “1”.

(3) Setting the count start flag to “0” causes the counter to hold its value and to stop.

Figure 2.3.4. Operation timing of timer mode

FFFF16

000016

Time

Count start flag

Timer Bi interrupt

request bit

“1”

n = reload register content

Set to “1” by software

“0”

Set to “1” by software

Cleared to “0” by

software

(2) Underflow

(3) Stop count

(1) Start count

Cleared to “0” when interrupt request is accepted, or cleared by software

Start count

again

M30620FCAFP Datasheet(PDF) 359 Page - Renesas Technology Corp