Datasheet

Section 7 ROM
Page 154 of 982 REJ09B0465-0300 Rev. 3.00
Sep 17, 2010
H8S/20103, H8S/20203, H8S/20223, H8S/20115, H8S/20215, H8S/20235 Group
7.2 Block Configuration
Figure 7.1 shows the blocks of the flash memory. The user ROM area contains the programmable
ROM area for storing the microcomputer's operating program and the data flash area for storing
data. In the figure, the thick-line frames each indicate an erasure block (erasing unit); the thin-line
frames each indicate a programming unit. The values in the frames are addresses. Erasure can be
done in erasure-block units shown in the figure 7.1. Programming can be done in 2-word or 4-byte
units, each of which begins at the address whose lower four-bit value is H'0, H'4, H'8, or H'C.