HD6412340 HITACHI [Hitachi Semiconductor], HD6412340 Datasheet - Page 546

• Manufacturer Part Number: HD6412340
• Description: H8S/2345 F-ZTAT Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

Section 16 RAM
16.1
Overview
The H8S/2345 and H8S/2344 have 4 kbytes of on-chip high-speed static RAM, and the H8S/2343,
H8S/2341, and H8S/2340 have 2 kbytes. The RAM is connected to the CPU by a 16-bit data bus,
enabling one-state access by the CPU to both byte data and word data. This makes it possible to
perform fast word data transfer.
The on-chip RAM of the H8S/2345 and H8S/2344 is allocated addresses H'EC00 to H'FBFF (4
kbytes) in the normal modes (modes 1 to 3)*, and addresses H'FFEC00 to H'FFFBFF (4 kbytes) in
the advanced modes (modes 4 to 7).
The on-chip RAM of the H8S/2343, H8S/2341, and H8S/2340 is allocated addresses H'F400 to
H'FBFF (2 kbytes) in the normal modes (modes 1 to 3)*, and addresses H'FFF400 to H'FFFBFF (2
kbytes) in the advanced modes (modes 4 to 7).
The on-chip RAM can be enabled or disabled by means of the RAM enable bit (RAME) in the
system control register (SYSCR).
Note: * ZTAT, mask ROM, and ROMless versions only.
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