Section 12 Timer B; Overview; Features; Block Diagram - Hitachi H8S/2199 Hardware Manual

12.1

Overview

Timer B is an 8-bit up-counter. Timer B is equipped with two different types of functions namely,
the interval function and the auto reloading function.
12.1.1

Features

• Seven different types of internal clocks (φ/16384, φ/4096, φ/1024, φ/512, φ/128, φ/32 and φ/8)
or an of external clock can be selected.
• When the counter overflows, a interrupt request will be issued.
12.1.2

Block Diagram

Figure 12.1 shows a block diagram of timer B.
Clock sources
φ/16384
φ/4096
φ/1024
φ/512
φ/128
φ/32
φ/8
TMBI
[Legend]
TMB : Timer mode register B
TCB : Timer counter B
TLB : Timer re-loading register B
TMBI : Event input terminal of the Timer B

Section 12 Timer B

Figure 12.1 Block Diagram of Timer B
TMB
TCB
Overflowing
Re-loading
TLB
Interrupting
Rev. 1.0, 02/00, page 253 of 1141
circuit
Timer B
Interrupt requests