HD6412350 Hitachi, HD6412350 Datasheet - Page 89

• Manufacturer Part Number: HD6412350
• Description: (HD6412350 / HD6432351) 16-BIT MICROCONTROLLER
• Manufacturer: Hitachi

3.1
3.1.1
The H8S/2350 has three operating modes (modes 1, 4, and 5). These modes are determined by the
mode pin (MD
as shown in table 3-1.
Table 3-1 lists the MCU operating modes.
Table 3-1
MCU
Operating
Mode
0
1
2
3
4
5
6
7
The CPU's architecture allows for 4 Gbytes of address space, but the H8S/2350 actually accesses a
maximum of 16 Mbytes.
Modes 1, 4, and 5 are externally expanded modes that allow access to external memory and
peripheral devices.
The external expansion modes allow switching between 8-bit and 16-bit bus modes. After program
execution starts, an 8-bit or 16-bit address space can be set for each area, depending on the bus
controller setting. If 16-bit access is selected for any one area, 16-bit bus mode is set; if 8-bit
access is selected for all areas, 8-bit bus mode is set.
Note that the functions of each pin depend on the operating mode.
Overview
H8S/2350 Operating Mode Selection
MD
0
1
MCU Operating Mode Selection (H8S/2350)
2
2
to MD
MD
0
1
0
1
Section 3 MCU Operating Modes
1
0
) settings. The CPU operating mode and initial bus width can be selected
MD
0
1
0
1
0
1
0
1
0
CPU
Operating
Mode
—
Normal
—
Advanced On-chip ROM disabled, Disabled 16 bits
—
Description
—
On-chip ROM disabled,
expanded mode
—
expanded mode
—
On-Chip
ROM
—
Disabled 8 bits
—
—
Initial
Width
—
—
8 bits
—
External Data Bus
Max.
Width
16 bits
—
16 bits
16 bits
—
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