Hitachi H8/300H Series Programming Manual page 13

(2) Advanced Mode: In advanced mode the exception vector table and stack structure differ from
the H8/300 CPU.
Address Space: Up to 16 Mbytes can be accessed linearly.
Extended Registers (En): The extended registers (E0 to E7) can be used as 16-bit data registers,
or they can be combined with the general registers (R0 to R7) for use as 32-bit data registers.
When a 32-bit register is used as an address register, the upper 8 bits are ignored.
Instruction Set: All additional instructions and addressing modes of the H8/300H can be used.
Exception Vector Table and Memory Indirect Branch Addresses: In advanced mode the top
area starting at H'000000 is allocated to the exception vector table in units of 32 bits. In each 32
bits, the upper 8 bits are ignored and a branch address is stored in the lower 24 bits (figure 1-4).
The exception vector table differs depending on the microcontroller, so see the relevant hardware
manual for further information.
H'000000
H'000003
H'000004
H'00000B
H'00000C
Figure 1-4 Exception Vector Table (advanced mode)
Don't care
Reset exception vector
Reserved for system use
Don't care
Exception vector
5
Exception vector table