PCA8515P Philips Semiconductors, PCA8515P Datasheet - Page 9

• Manufacturer Part Number: PCA8515P
• Description: Stand-alone OSD
• Manufacturer: Philips Semiconductors

Philips Semiconductors
7
256 character fonts may be held in ROM; 253 customer
selected fonts and three reserved character font codes.
Customer selected fonts are mask programmable. Each
character font is stored in a 12
in Fig.5. Elements in Rows 1 to 18 can be selected as
visible dots on the screen; Row 0 is used only for the
combination of two characters in a vertical direction, when
North-West shadowing mode is selected (see
Sections 9.9 and 10.2). Extremely high resolution can be
achieved by having no spacing between characters on the
same line and by programming the inter-line spacing to
zero. The 12
semigraphic patterns, Kanji, Hiragana, Katagana or even
Chinese characters.
7.1
Figure 6 shows the character font address map in ROM
and RAM. Addresses FFH and FEH hold the reserved
codes for space and carriage return functions respectively;
address FDH is reserved for testing purposes and
addresses (00H to FCH) contain the character font codes.
7.2
ROM is divided into two parts; ROM1 and ROM2. The
organization of the bit patterns stored in ROM1 and ROM2
is shown in Fig.7.
1995 Jan 19
Stand-alone OSD
CHARACTER FONTS
Character font address map
Character font ROM
Fig.5 Character dot matrix organization.
10
11
12
13
14
15
16
17
18
0
1
2
3
4
5
6
7
8
9
11
18 dot matrix is suitable for the display of
10
9
8
7
6
5
4
19 dot matrix, as shown
3
2
MLC350
1
0
9
The file format to submit to Philips for customized
character sets is also shown in Fig.7. The following points
should be noted.
1. Row 0 of each font is reserved for vertical combination
2. When two font cells are combined in a vertical
3. Binary 1 denotes visual dots; binary 0 denotes a blank
4. ROM1 and ROM2 data files are in INTEL hex format
5. The remaining unused 16 bytes (one character font) in
6. CS denotes Checksum.
A software package (OSDGEM) that assists in the design
of character fonts on-screen and that also automatically
generates the bit pattern HEX files, is available on request.
The package is run under the MS-DOS environment for
IBM compatible PCs.
of two fonts.
direction Row 0 of the lower font must contain the
same bit pattern as held in Row 18 of the character
above it.
space.
on a byte basis. Each byte is structured High nibble
followed by Low nibble.
ROM1/ROM2 must be filled with FFH.
reserved code
254 (FEH)
255 (FFH)
253 (FDH)
252 (FCH)
Fig.6 ROM address map.
0
Mask Programmable Font
Carriage return code
Space code
Test code
Preliminary specification
PCA8515
MLB344