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ST92195 ST92T195 ST92E195 - ON SCREEN DISPLAY (OSD)
ON SCREEN DISPLAY (Cont’d)
7.4.7 Font Mapping
The font consists of two character sets of 512
characters each. Only one set can be accessed at
the same time. The FRSW bit of the NCSR regis-
ter allows to switch from one set to the other.
G0 is the basic character font.
G1 is the mosaic font. It is not stored in ROM but is
implemented in hardware. In serial mode it is ad-
dressed by a serial attribute (See Table 20. on
page 104). In parallel mode it is accessed by bit 0
(CSS) of the parallel shape attribute and bit 1 (US)
for separated mosaic (See Table 21. on page
108).
G2 is a font of X/26 based + Menu shared charac-
ters.
An Extended Menu character font available in par-
allel mode. It is accessed via bit 0 (CSS) in the par-
allel shape attribute (Character Set Selection).
The Extended Menu font is not accessible in serial
mode.
7.4.8 Font Mapping Modes
There are two font mapping modes selected by the
NCM bit in the NCSR register R245 (F5h) Page
32:
Single G0 mode
A set combining 83 characters from
the G0 basic set plus 13 characters
selected from 15 National character
subsets. The National character sub-
sets are selected by four bits (NC3:0)
in the NCSR register R245 (F5h)
Page 32.
Triple G0 mode
Three 96-character character sets
(G0-0, G0-1 and G0-2) for multi al-
phabet applications. Character set
selection is done by four bits (NC1:0
or NC3:2) in the NCSR register R245
(F5h) Page 32.
– In Serial Mode (Level 1), only 256 Character
Codes are available using an 8-bit code. The
character codes plus some serial attributes and
some additional programmable options address
566 chars: 256 + 182 NS chars + 128 mosaics in
single G0 mode.
– In Parallel Mode (Enhanced Level 1), 512 Char-
acter Codes are available using a 9-bit code. The
character codes plus some serial and parallel at-
tributes, and some additional programmable op-
tions address 662 chars: 256 + 182 NS chars +
128 mosaic + 96 extended chars. in single G0
mode.
Display ROM Font Entry:
The user must define his own fonts for each set of
characters:
– 278 characters: - 15 x 13 G0 National Character
subsets + 83 G0 Character set
or
– 288 characters: 3 x 96-character character sets
– 128 G2 based X/26 and Menu characters
– 96 Extended Menu characters
Table 24. Triple G0 Mode - Font Mapping
ROM
Address
Character
Code
CSS
Font Usage
000h to 01Fh 0E0h to 0FFh
1
Extended menu
020h to 07Fh 020h to 07Fh
0
(or serial
mode)
G0 set 0
080h to 0FFh 080h to 0FFh
G2 + Menu
100h to 15Fh 020h to 07Fh
G0 set 1
160h to 1BFh 020h to 07Fh
G0 set 2
1C0h to 1FFh 0A0h to 0DFh
1
Extended menu