Renesas H8 Series Hardware Manual page 188

Section 6 ROM
Note: *
The output data is not guaranteed if this address area is read in PROM mode.
Therefore, when programming with a PROM programmer, be sure to specify
addresses from H'0000 to H'7FFF. If programming is inadvertently performed from
H'8000 onward, it may not be possible to continue PROM programming and
verification.
When programming, H'FF should be set as the data in this address area (H'8000 to
H'1FFFF).
Rev. 7.00 Mar 10, 2005 page 146 of 652
REJ09B0042-0700
Address in
MCU mode
H'0000
H'7FFF
Figure 6.3 H8/38024 Memory Map in PROM Mode
Address in
PROM mode
H'0000
On-chip PROM
H'7FFF
Uninstalled area *
H'1FFFF