M37221M4H_15 Datasheet, PDF (67/114 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER

M37221M4H/M6H/M8H/MAH–XXXSP/FP M37221EASP/FP
8.11.4 Memory for OSD
There are 2 types of memory for OSD: OSD ROM (addresses 1000016
to 11FFF16) used to store character dot data and OSD RAM (ad-
dresses 060016 to 06B716) used to specify the characters and colors
to be displayed.
(1) OSD ROM (addresses 1000016 to 11FFF16)
The dot pattern data for OSD characters is stored in the OSD ROM.
To specify the kinds of character font, it is necessary to write the
character code (Table 8.11.3) into the OSD RAM.
The OSD ROM has a capacity of 8K bytes. Since 32 bytes are re-
quired for 1 character data, the ROM can stores up to 256 kinds of
characters.
The OSD ROM space 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 and 1100016 to 117FF16 ;
the [vertical 16 dots] ✕ [horizontal (right side) 4 dots] data of display
characters are stored in addresses 1080016 to 10FFF16 and 1180016
to 11FFF16 (refer to Figure 8.11.11). Note however that the high-
order 4 bits in the data to be written to addresses 1080016 to 10FFF16
and 1180016 to 11FFF16 must be set to “1” (by writing data “FX16”).
Data of the character font is specified shown in Figure 8.11.11.
10XX016
or
11XX016
10XXF16
or
11XXF16
b7
b0
00000000
00000100
00000100
00001010
00001010
00010001
00010001
00010001
00100000
00100000
00111111
01000000
01000000
01000000
00000000
00000000
Fig. 8.11.11 Character Font Data Storing Address
Rev.1.00 Oct 01, 2002 page 65 of 110
REJ03B0134-0100Z
b7
b3
b0
10XX016
+80016
or
11XX016
+80016
11110000
11110000
11110000
11110000
11110000
11110000
11110000
11110000
11111000
11111000
11111000
11110100
11110100
11110100
11110000
10XXF16
+80016
or
11XXF16
+80016
11110000