4570 Datasheet, PDF (13/69 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
4570 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
DATA MEMORY (RAM)
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 Z, X, and Y. Set a
value to the data pointer certainly when executing an instruction
to access RAM.
Table 2 shows the RAM size. Figure 12 shows the RAM map.
Table 2 RAM size
Product
M34570Mx
M34570Ex
RAM size
128 words ! 4 bits (512 bits)
Fig. 12 RAM map
RAM 128 words ! 4 bits (512 bits)
Register Z
0
Register X 0 ₁ 2 3 ^... 6 7
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
128 words
12