HD64F2149 Datasheet, PDF (687/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

Section 21 RAM
21.1 Overview
The H8S/2169 or H8S/2149 has 2 kbytes of on-chip high-speed static RAM. The on-chip RAM is
connected to the bus master by a 16-bit data bus, enabling both byte data and word data to be
accessed in one state. This makes it possible to perform fast word data transfer.
The on-chip RAM can be enabled or disabled by means of the RAM enable bit (RAME) in the
system control register (SYSCR).
21.1.1 Block Diagram
Figure 21.1 shows a block diagram of the on-chip RAM.
Internal data bus (upper 8 bits)
Internal data bus (lower 8 bits)
H'FFE880
H'FFE882
H'FFE884
H'FFE881
H'FFE883
H'FFE885
H'FFEFFE
H'FFFF00
H'FFEFFF
H'FFFF01
H'FFFF7E
H'FFFF7F
Figure 21.1 Block Diagram of RAM
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