HD643303x Hitachi, HD643303x Datasheet - Page 70

• Manufacturer Part Number: HD643303x
• Description: Hitachi Microcomputer
• Manufacturer: Hitachi

3.1 Overview
3.1.1 Operating Mode Selection
The H8/3032 Series has three operating modes (modes 1 to 3) that are selected by the mode pins
(MD
single-chip mode.
Table 3-1 Operating Mode Selection
Operating Mode
—
Mode 1
Mode 2
Mode 3
Notes: 1. In mode 1, if the RAM enable bit (RAME) in the system control register (SYSCR) is
For the address space size there are two choices: 64 kbytes or 1 Mbyte.
Modes 1 and 3 support a maximum address space of 1 Mbyte. Mode 2 supports a maximum
address space of 64 kbytes.
The H8/3032 Series can only be used in modes 1 to 3. The inputs at the mode pins must select one
of these three modes. The inputs at the mode pins must not be changed during operation.
1
and MD
2. In modes 2 and 3, clearing bit RAME of SYSCR to 0 and reading the on-chip RAM
cleared to 0, these addresses become external addresses.
always returns H’FF, and write access is ignored. For details, see section 13.3,
Operation.
0
) as indicated in table 3-1. The input at these pins determines expanded mode or
Section 3 MCU Operating Modes
MD
0
0
1
1
Mode Pins
1
MD
0
1
0
1
0
Address Space
—
1 Mbyte
64 kbytes
1 Mbyte
55
Initial Bus Width
—
8 bits
—
—
Description
*1
On-Chip RAM
—
Enabled
Enabled
Enabled
*1
*2
*2