HD6433044 Datasheet, PDF (579/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

18.4.2 Mode Programming and Flash Memory Address Space
As its on-chip ROM, the H8/3048F has 128 kbytes of flash memory. The flash memory is
connected to the CPU by a 16-bit data bus. The CPU accesses both byte data and word data in
two states.
The flash memory is assigned to addresses H'00000 to H'1FFFF on the memory map. The mode
pins enable either on-chip flash memory or external memory to be selected for this area. Table
18-8 summarizes the mode pin settings and usage of the flash memory area.
Table 18-8 Mode Pin Settings and Flash Memory Area
Mode
Mode 0
Mode 1
Mode 2
Mode 3
Mode 4
Mode 5
Mode 6
Mode 7
MD₂
0
0
0
0
1
1
1
1
Mode Pin Setting
MD₁
0
MD₀
0
0
1
1
0
1
1
0
0
0
1
1
0
1
1
Flash Memory Area Usage
Illegal setting
External memory area
External memory area
External memory area
External memory area
On-chip flash memory area
On-chip flash memory area
On-chip flash memory area
18.4.3 Features
Features of the flash memory are listed below.
• Five flash memory operating modes
The flash memory has five operating modes: program mode, program-verify mode, erase
mode, erase-verify mode, and prewrite-verify mode.
• Block erase designation
Blocks to be erased in the flash memory address space can be selected by bit settings. The
address space includes a large-block area (eight blocks with sizes from 12 kbytes to 16 kbytes)
and a small-block area (eight 512-byte blocks).
• Program and erase time
Programming one byte of flash memory typically takes 50 µs. Erasing all blocks (128 kbytes)
typically takes 1 s.
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