4283 Group
PROGRAM MEMORY (ROM)
The program memory is a mask ROM. 1 word of ROM is
composed of 9 bits. ROM is separated every 128 words by the
unit of page (addresses 0 to 127).
8
7
6
5
4
3
2
1 0
000016
Page 0
Page 1
Page 2
Page 3
00801166
007
F
00FF
01001166
Table 1 ROM size and pages
Subroutine special page
Part number
M34283G2
ROM size (✕ 9 bits)
Pages
017F16
018016
2048 words
16 (0 to 15)
Page 2 (addresses 010016 to 017F16) is the special page for
subroutine calls. Subroutines written in this page can be called
from any page with the 1-word instruction (BM). Subroutines
extending from page 2 to another page can also be called with
the BM instruction when it starts on page 2.
07FF16
Page 15
Fig. 10 ROM map of M34283G2
ROM pattern of all addresses can be used as data areas with
the TABP p instruction.
DATA MEMORY (RAM)
RAM 64 words ✕ 4 bits (256 bits)
1 word of RAM is composed of 4 bits, but 1-bit manipulation
(with the SB j, RB j, and SZB j instructions) is enabled for the
entire memory area. A RAM address is specified by a data
pointer. The data pointer consists of registers X and Y. Set a
value to the data pointer certainly when executing an instruction
to access RAM.
Register X
0
2 3
1
0
1
2
3
Table 2 shows the RAM size. Figure 11 shows the RAM map.
4
Table 2 RAM size
5
Part number
M34283G2
RAM size
6
64 words ✕ 4 bits (256 bits)
7
8
9
10
11
12
13
14
15
64 words
M34283G2
Fig. 11 RAM map
Rev.1.01 Mar 20, 2006 page 10 of 62
REJ03B0109-0101
RENESAS [ RENESAS TECHNOLOGY CORP ]
