7220 Datasheet, PDF (159/303 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

M37220M3-XXXSP/FP
4.5 Functional description
(1) Memory for display
There are 2 types of display memory: CRT display ROM (addresses 1000016 to 10FFF16) and CRT
display RAM (addresses 060016 to 06B316). Each type of display memory is described below.
s CRT display ROM (addresses 1000016 to 10FFF16)
CRT display ROM has a capacity of 4 K bytes. Since 32 bytes are required for 1 character data,
the ROM can stores up to 128 kinds of characters.
CRT display ROM is broadly divided into 2 areas. The [vertical 16 dots] ! [horizontal (left side)
8 dots] data of display characters are stored in addresses 1000016 to 107FF16 ; the [vertical 16
dots] ! [horizontal (right side) 4 dots] data of display characters are stored in addresses 1080016
to 10FFF16 (refer to “Figure 4.5.11”). Note however that the high-order 4 bits of the data to be
written to addresses 1080016 to 10FFF16 must be set to “1” (by writing data FX16).
10XX016
10XXF16
b7
b0
00000000
00000100
00 00 01 00
00 0 0 1 0 10
00 0 0 1 0 10
00 0 1 0 0 01
00 0 1 0 0 01
00 01 00 01
00100000
00100000
00111111
01000000
01 00 00 00
01 00 00 00
00 00 00 00
00 0 0 0 0 00
10XX016
+80016
10XXF16
+80016
b7
b3
b0
11110000
11110000
11110000
11110000
11110000
11110000
11110000
11110000
11111000
11 11 10 00
11 11 10 00
11110100
11110100
11110100
11110000
111 1 00 00
Fig. 4.5.11 Example of display character data storing form
7220 Group User’s Manual
4-21