Section 10 Timer A; Features - Renesas H8 Series Hardware Manual

Timer A is an 8-bit timer with interval timing and real-time clock time-base functions. The clock
time-base function is available when a 32.768kHz crystal oscillator is connected. Figure 10.1
shows a block diagram of timer A.
10.1

Features

• Timer A can be used as an interval timer or a clock time base.
• An interrupt is requested when the counter overflows.
• Any of eight clock signals can be output from pin TMOW: 32.768 kHz divided by 32, 16, 8, or
4 (1 kHz, 2 kHz, 4 kHz, 8 kHz), or the system clock divided by 32, 16, 8, or 4.
Interval Timer
• Choice of eight internal clock sources (φ/8192, φ/4096, φ/2048, φ/512, φ/256, φ/128, φ/32, φ8)
Clock Time Base
• Choice of four overflow periods (1 s, 0.5 s, 0.25 s, 31.25 ms) when timer A is used as a clock
time base (using a 32.768 kHz crystal oscillator).

Section 10 Timer A

Section 10 Timer A
Rev. 1.00 Aug. 28, 2006 Page 143 of 400
REJ09B0268-0100