Section 9 I/O Ports; Overview; Block Diagram - Hitachi H8/3152 Hardware Manual

9.1

Overview

The H8/3150 series has two I/O ports. Software can select whether to use each I/O bit for data
input or output.
The I/O ports have a data register (DR) for latching output data, and a data direction register
(DDR) for specifying input or output.
9.1.1

Block Diagram

Figure 9.1 shows an I/O port block diagram. DR and DDR can be accessed only by byte access.

Section 9 I/O Ports

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