Hardware manual

Microcomputer Technical Q&A
134
Q&A No.: QAH8S-246
Category: I/O Ports
Subject: I/O Port Manipulation
Question
When a particular bit of an I/O port is specified as an output port, can a bit-manipulation
instruction be executed on that port?
Answer
Yes. The port data registers (DRs) can be read or written to at any time, and can be manipulated
with bit-manipulation instructions.
The data direction registers (DDRs) are write-only registers, and so cannot be manipulated with
bit-manipulation instructions.
Applicable Products
Applicability Series Applicability Series Applicability Series
Yes Entire H8S Series H8S/2655 H8S/2350
H8S/2355 H8S/2357 H8S/2345
H8S/2245 H8S/2148 H8S/2144
H8S/2138 H8S/2134 H8S/2128
H8S/2124 — — — —