Hardware manual

Microcomputer Technical Q&A
10
Q&A No.: QAH8S-009
Category: Instruction
Subject: BRN Instruction
Question
What kind of instruction is BRN (BF)?
Answer
The BRN instruction is useful as a replacement for a conditional branch instruction during
debugging.
The operation of the BRN instruction is similar to that of the NOP instruction, but the instruction
size and instruction execution time are different, as shown below.
Instruction Instruction Size (Bytes) Instruction Execution Time (States)
BRN d:8 2 2
*
d:16 4 3
*
NOP 2 1
*
Note: * When the instruction is fetched from on-chip ROM
Note: Like BRN, the BRA (BT) instruction is useful for debugging, etc.
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 — — — —