HD6413003RF Datasheet, PDF (75/715 Pages) Renesas Technology Corp – Microcontroller (MCU)

Section 3 MCU Operating Modes
3.1 Overview
3.1.1 Operating Mode Selection
The H8/3003 has four operating modes (modes 1 to 4) that are selected by the mode pins (MD₂ to
MD₀) as indicated in table 3-1. The input at these pins determines the size of the address space
and the initial bus mode.
Table 3-1 Operating Mode Selection
Mode Pins
Description
Operating Mode MD₂ MD₁ MD₀ Address Space
—
000
—
Initial Bus Mode^*1
—
On-Chip RAM
—
Mode 1
001
1 Mbyte
8 bits
Enabled^*2
Mode 2
010
1 Mbyte
16 bits
Enabled^*2
Mode 3
011
16 Mbytes
8 bits
Enabled^*2
Mode 4
100
16 Mbytes
16 bits
Enabled^*2
—
101
—
—
—
—
110
—
—
—
—
111
—
—
—
Notes: 1. In all modes, an 8-bit or 16-bit data bus can be selected on a per-area basis by settings
made in the area bus width control register (ABWCR). For details see section 6, Bus
Controller.
2. If the RAM enable bit (RAME) in the system control register (SYSCR) is cleared to 0,
these addresses become external addresses.
For the address space size there are two choices: 1 Mbyte or 16 Mbytes. The external data bus is
either 8 or 16 bits wide depending on the settings in the area bus width control register (ABWCR).
If 8-bit access is selected for all areas, the external data bus is 8 bits wide. For details see
section 6, Bus Controller.
Modes 1 to 4 are externally expanded modes that enable access to external memory and peripheral
devices. Modes 1 and 2 support a maximum address space of 1 Mbyte. Modes 3 and 4 support a
maximum address space of 16 Mbytes.
The H8/3003 can only be used in modes 1 to 4. The inputs at the mode pins must select one of
these four modes. The inputs at the mode pins must not be changed during operation.
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