Hardware manual

Microcomputer Technical Q&A
15
Q&A No.: QAH8S-014
Category: Instruction
Subject: Stack Precautions
Question
Are any precautions required concerning the stacking method?
Answer
The CPU always uses word-size or longword-size access to the stack area. Setting the SP (stack
pointer) to an odd value may result in misoperation. The PUSH, POP, STM, and LDM instructions
should be used for stacking.
The initial value of the stack pointer is undefined, and must be set by the user.
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 — — — —