6V7 datasheet(195/298 Pages) RENESAS

195 / 298 page

Rev.1.00

May 18, 2004

page 195 of 296

M306V7MG/MH/MJ/MJA-XXXFP, M306V7FG/FH/FJ/FJAFP

2.16.6 Memory for OSD

There are 2 types of memory for OSD : OSD ROM (addresses 4000016 to 5FFFF16) used to store char-

acter dot data and OSD RAM (addresses 040016 to 13FF16) used to specify the kinds of display charac-

ters, display colors, and SPRITE display. The following describes each type of memory.

(1) ROM for OSD (addresses 4000016 to 5FFFF16)

The dot pattern data for OSD characters is stored in the character font area in the OSD ROM and the

CD font data for OSD characters is stored in the color dot font area in the OSD ROM. To specify the

kinds of the character font and the CD font, it is necessary to write the character code into the OSD

RAM.

For character font, there are the following 2 mode.

• OSDL enable mode

16 ✕ 20-dot font and 24 ✕ 32-dot font

• OSDL disable mode

16 ✕ 20-dot font

The modes are selected by bit 0 of the OSD control register 4 for each screen.

The conditions for each OSDL enable/disable mode are shown in Figure 2.16.22.

During OSDL enable mode, character codes 00016 through 1FF16 can be used. In this case, the

character codes 00016 through 0FF16 are turned to 16 ✕ 20-dot fonts, whereas the character codes

10016 through 1FF16 are turned to 24 ✕ 32- dot fonts. Of these, however, character codes 0FE16,

0FF16, 10016, and 18016 cannot be used.

During OSDL disable mode, character codes 00016 through 2FF16 can be used. In this case, all

characters are turned to 16 ✕ 20-dots. Of these, however, character codes 0FE16, 0FF16, 10016,

18016, 20016, and 0FE16 cannot be used.

CD codes 0016 through 7F16 can be used. In this case, all characters are turned to 16 ✕ 26-dot fonts.

Of these, however, CD codes 3F16 and 4016 cannot be used.

Figure 2.16.21 OSD control register 4

OSD control register 4

Symbol

Address

When reset

OC4

025F16

XXXXX002

Bit name

Bit symbol

Function

OC40

OC41

OSDL mode

selection bit

Number of horizontal

display characters

selection bit

0 : OSDL enable mode

1 : OSDL disable mode

0 : 32 characters for each block

(32-character mode)

1 : 42 characters for each block

(42-character mode)

Nothing is assigned.

In an attempt to write to these bits, write “0.” The value, if read, turns out to be “0.”

6V7 Datasheet(PDF) 195 Page - Renesas Technology Corp

6V7 Datasheet(HTML) 195 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL