7702 datasheet(108/217 Pages) RENESAS

108 / 217 page

TIMER A

7702/7703 Group User’s Manual

5–20

5.4 Event counter mode

Item

Count source

Count operation

Divide ratio

Count start condition

Count stop condition

Interrupt request occurrence timing

TAjIN, TAjOUT (j = 2 to 4) pin function

Read from timer Aj register

Write to timer Aj register

Table 5.4.2 Specifications of event counter mode (when using two-phase pulse signal processing

function with timers A2, A3, and A4)

(n + 1)

n: Timer Aj register setting value

Specifications

External signal (two-phase pulse) input to the TAjIN or TAjOUT pin (j =

2 to 4)

q Up-count or down-count can be switched by external signal (two-

phase pulse).

q When the counter overflows or underflows, reload register’s contents

are reloaded and counting is continued.

q For down-count

q For up-count

When count start bit is set to “1.”

When count start bit is cleared to “0.”

When the counter overflows or underflows.

Two-phase pulse input

Counter value can be read out.

q While counting is stopped

When a value is written to timer A2, A3, or A4 register, it is written

to both reload register and counter.

q While counting is in progress

When a value is written to timer A2, A3, or A4 register, it is written

to only reload register. (Transferred to counter at next reload time.)

(FFFF16 – n + 1)

7702 Datasheet(PDF) 108 Page - Renesas Technology Corp