M37221M4H/M6H/M8H/MAH–XXXSP/FP M37221EASP/FP
8.11 OSD FUNCTIONS
Table 8.11.1 outlines the OSD functions. This microcomputer incor-
porates an OSD control circuit of 24 characters ✕ 2 lines. OSD is
controlled by the CRT control register. Up to 256 kinds of characters
can be displayed. The colors can be specified for each character and
up to 4 kinds of colors can be displayed on one screen. A combina-
tion of up to 8 colors can be obtained by using each output signal (R,
G, and B).
Characters are displayed in a 12 ✕ 16 dots configuration to obtain
smooth character patterns (refer to Figure 8.11.1).
The following shows the procedure how to display characters on the
CRT screen.
✕ Write the display character code in OSD RAM.
✕ Specify the display color by using the color register.
✕ Write the color register in which the display color is set in OSD
RAM.
✕ Specify the vertical position by using the vertical position register.
✕ Specify the character size by using the character size register.
✕ Specify the horizontal position by using the horizontal position
register.
✕ Write the display enable bit to the designated block display flag of
the CRT control register. When this is done, the OSD starts ac-
cording to the input of the VSYNC signal.
Table 8.11.1 Features of Each Display Mode
Parameter
Functions
Number of display characters
Dot structure
24 characters ✕ 2 lines
12 ✕ 16 dots
256 kinds
Kinds of characters
Kinds of character sizes
Attribute
3 kinds
Border (black)
Character font coloring
Character background coloring
OSD output
1 screen : 8 kinds (per character unit)
1 screen : 8 kinds (per character unit)
R, G, B
Display position
Horizontal: 64 levels, Vertical: 128 levels
Possible
Display expansion (multiline display)
Rev.1.00 Oct 01, 2002 page 54 of 110
REJ03B0134-0100Z
RENESAS [ RENESAS TECHNOLOGY CORP ]
