Datasheet
Rev.6.00 Oct.28.2004 page 565 of 1016
REJ09B0138-0600H
19.3 Operation
The on-chip ROM is connected to the CPU by a 16-bit data bus, and both byte and word data can be accessed in one state.
Even addresses are connected to the upper 8 bits, and odd addresses to the lower 8 bits. Word data must start at an even
address.
The on-chip ROM is enabled and disabled by setting the mode pins (MD
2
, MD
1
, and MD
0
) and bit EAE in BCRL. These
settings are shown in tables 19-2 and 19-3.
Table 19-2 Operating Modes and ROM Area (H8S/2357 F-ZTAT)
Mode Pin BCRL
Operating Mode FWE MD
2
MD
1
MD
0
EAE On-Chip ROM
Mode 0 — 0000 ——
Mode 1 1
Mode 2 1 0
Mode 3 1
Mode 4 Advanced expanded mode
with on-chip ROM disabled
1 0 0 — Disabled
Mode 5 Advanced expanded mode
with on-chip ROM disabled
1
Mode 6 Advanced expanded mode 1 0 0 Enabled (128 kbytes)*
1
with on-chip ROM enabled
1 Enabled (64 kbytes)
Mode 7 Advanced single-chip mode 1 0 Enabled (128 kbytes)*
1
1 Enabled (64 kbytes)
Mode 8 — 1000 ——
Mode 9 1
Mode 10 Boot mode (advanced 1 0 0 Enabled (128 kbytes)*
2
expanded mode with on-
chip ROM enabled)*
3
1 Enabled (64 kbytes)
Mode 11 Boot mode (advanced 1 0 Enabled (128 kbytes)*
2
single-chip mode)*
4
1 Enabled (64 kbytes)
Mode 12 — 1 0 0 — —
Mode 13 1
Mode 14 User program mode
(advanced expanded mode
1 0 0 Enabled (128 kbytes)*
1
with on-chip ROM
enabled)*
3
1 Enabled (64 kbytes)
Mode 15 User program mode 1 0 Enabled (128 kbytes)*
1
(advanced single-chip
mode)*
4
1 Enabled (64 kbytes)
Notes: 1. Note that in modes 6, 7, 14, and 15, the on-chip ROM that can be used after a power-on reset is the 64-kbyte
area from H'000000 to H'00FFFF.
2. Note that in the mode 10 and mode 11 boot modes, the on-chip ROM that can be used immediately after all
flash memory is erased by the boot program is the 64-kbyte area from H'000000 to H'00FFFF.
3. Apart from the fact that flash memory can be erased and programmed, operation is the same as in advanced
expanded mode with on-chip ROM enabled.
4. Apart from the fact that flash memory can be erased and programmed, operation is the same as in advanced
single-chip mode.