HD6432670 Hitachi, HD6432670 Datasheet - Page 107

• Manufacturer Part Number: HD6432670
• Description: (HD64F267x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

3.3
3.3.1
The CPU can access a 16-Mbyte address space in advanced mode. The on-chip ROM is disabled.
Ports A, B, and C function as an address bus, ports D and E function as a data bus, and parts of
ports F, G, and H carry bus control signals.
The initial bus mode after a reset is 16 bits, with 16-bit access to all areas. However, if 8-bit access
is designated for all areas by the bus controller, the bus mode switches to 8 bits.
3.3.2
The CPU can access a 16-Mbyte address space in advanced mode. The on-chip ROM is disabled.
Ports A, B, and C function as an address bus, ports D and E function as a data bus, and parts of
ports F, G, and H carry bus control signals.
The initial bus mode after a reset is 8 bits, with 8-bit access to all areas. However, if 16-bit access
is designated for all areas by the bus controller, the bus mode switches to 16 bits and port E
functions as a data bus.
3.3.3
This mode is a boot mode of the flash memory. This mode is the same as mode 7, except for
accessing to the flash memory. Mode 3 is available only in the flash memory version of the
H8S/2678R Series.
3.3.4
The CPU can access a 16-Mbyte address space in advanced mode. The on-chip ROM is enabled.
The program in the on-chip ROM connected to the first half of area 0 is executed.
Ports A, B, and C function as input ports immediately after a reset, but can be set to function as an
address bus. For details, see section 10, I/O Ports. Ports D and E function as a data bus, and parts
of ports F, G, and H carry bus control signals.
The initial bus mode after a reset is 8 bits, with 8-bit access to all areas. However, if 16-bit access
is designated for any area by the bus controller, the bus mode switches to 16 bits and port E
functions as a data bus. In the flash memory version, user program mode is entered by setting 1 to
the SWE bit of FLMCR1.
Operating Mode Descriptions
Mode 1
Mode 2
Mode 3
Mode 4
Rev. 2.0, 04/02, page 61 of 906