Section 8 Rom (H8S/2194C Series); Overview; Block Diagram - Renesas Hitachi H8S/2194 Series Hardware Manual

Section 8 ROM (H8S/2194C Series)

8.1

Overview

The H8S/2194C has 256 kbytes of on-chip ROM (flash memory or mask ROM), the H8S/2194B
has 192 kbytes, the H8S/2194A has 160 kbytes. The ROM is connected to the CPU by a 16-bit
data bus. The CPU accesses both byte and word data in one state, enabling faster instruction
fetches and higher processing speed.
The flash memory versions of the H8S/2194C can be erased and programmed on-board as well
as with a general-purpose PROM programmer.
8.1.1

Block Diagram

Figure 8.1 shows a block diagram of the ROM.
Internal data bus (upper 8 bits)
Internal data bus (lower 8 bits)
H'000000
H'000002
H'03FFFE
Figure 8.1 ROM Block Diagram (H8S/2194C)
H'000001
H'000003
H'03FFFF
Rev. 2.0, 11/00, page 171 of 1037