Differences From H8/300 Cpu; Cpu Operating Modes - Hitachi H8/3008 Hardware Manual

• Two CPU operating modes
 Normal mode
 Advanced mode
• Low-power mode
Transition to power-down state by SLEEP instruction
2.1.2

Differences from H8/300 CPU

In comparison to the H8/300 CPU, the H8/300H has the following enhancements.
• More general registers
Eight 16-bit registers have been added.
• Expanded address space
 Advanced mode supports a maximum 16-Mbyte address space.
 Normal mode supports the same 64-kbyte address space as the H8/300 CPU.
• Enhanced addressing
The addressing modes have been enhanced to make effective use of the 16-Mbyte address
space.
• Enhanced instructions
 Data transfer, arithmetic, and logic instructions can operate on 32-bit data.
 Signed multiply/divide instructions and other instructions have been added.
2.2

CPU Operating Modes

The H8/300H CPU has two operating modes: normal and advanced. Normal mode supports a
maximum 64-kbyte address space. Advanced mode supports up to 16 Mbytes.
CPU operating modes
18
Normal mode
Advanced mode
Figure 2.1 CPU Operating Modes
Maximum 64 kbytes, program
and data areas combined
Maximum 16 Mbytes, program
and data areas combined