HD64F3437TF16 Datasheet, PDF (528/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

Section 21 ROM
(60-kbyte Single-Power-Supply Flash Memory Version)
21.1 Flash Memory Overview
21.1.1 Mode Pin Settings and ROM Space
The H8/3437SF has 60 kbytes of on-chip flash memory. The ROM is connected to the CPU by a
16-bit data bus. The CPU accesses both byte data and word data in two states. 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.
Enabling and disabling of the on-chip ROM is performed by the mode pins (MD₁ and MD₂) and
the EXPE bit in MDCR.
The H8/3437SF flash memory can be programmed and erased on-board as well as with a PROM
programmer.
Table 21.1 Mode Pin Settings and ROM Space
MCU Operating
Mode
Mode 1
Mode 2
Mode 3
Operating Mode
Description
Expanded mode with on-chip ROM disabled
Expanded mode with on-chip ROM enabled
Single-chip mode
Mode Pin Settings
On-Chip
MD₁
MD₀
ROM
0
1
Disabled
1
0
Enabled
1
Enabled
499