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0000
0014
0014
0040
0040
007C
007C
0108
0108
010C
010C
0410
0410
0410
0449
0449
044A
044C
044E
0450
7???
????
08 {
0460
....
0462
..
0463
....
0465
??
0466
0472
0472
????
0484
0484
..
0485
????
0487
..
0488
??
04A8
04A8
????
379
380
381
382
383
384
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386
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388
389
390
391
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395
396
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4'81
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C
C
C
ENDIF
ENDM
C
; ----- LOW MEMORY SEGMENT
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ABSO
SEGMENT AT
ORG
005H*4
;
PR I NT SCREEN VECTOR
INT5_PTR
LABEL
DWORD
ORG
010H*4
; V IDEO I/O VECTOR
VIDEO
LABEL
DWORD
ORG
01 FH*4
; GRAPH I C CHARS 128-255
EXT_PTR
LABEL
DWORD
ORG
042H*4
; REVECTORED 10H*4
PLANAR_VIDEO
LABEL
DWORD
ORG
043H*4
;. GRAPH I C CHARS 0-255
GRX_SET
LABEL
DWORD
ORG
0410H
equip_loW'
labe I
byte
EQUIPJLAG
OW
?
;----- REUSE flAM FROM PLANAR BIOS
ORG
CRT MOOE
CRT-COLS
CRT-LEN
CRT-START
CURSOR_POSH
CURSOR_MODE
ACT IVE_PAGE
ADDR 6845
CRT MODE SET
CRT::PALETTE
ORG
RESET FLAG
-
ORG
ROWS
DB
POINTS
OW
INFO
DB
INFO
449H
DB
DW
DW
DW
OW
DW
DB
DW
DB
DB
0472H
DW
0484H
?
8 DUP(?)
ROWS ON THE SCREEN
BYTES PER CHARACTER
D7 - HIGH BIT OF MODE SET. CLEAR/NOT CLEAR REGEN
INFO 3
D6 - MEMORY
D6 D5 = 0 0 - 064K
0 1 - 128K
05 - MEMORY
1
0 -
192K
1 1 - 256K
D4 - RESERVED
D3 -
ega active monitor
(0),
ega not active
(1)
02 -
wa
it
fa r
d
i
sp
I
ay ena
b I
e
(1)
Dl - EGA HAS A MONOCHROME ATTACHED (1)
DO -
set c_type
emulate active (0)
-
07-04
D3-DO
FEATURE BITS
SWI TCHES
04a8h
labe I
dword
save_ptr Is 8 pointer to a table 8S described as follows:
dword 1
dword-2
dword-3
dword-4
dword::5
dword 6
dword::l
video parameter table pointer
dynam i c save
8
rea po i nte r
a Ipha mode Buxi I isry char gen pointer
graphics mode
BUX!
Ilary char gan pointer
reserved
reserved
reserved
Parameter Table Pointer
Initial ized to BIOS EGA parameter table.
Th
i s va
I
ue
MUST
ex
1st.
Parameter Save area pointer
Initialized to 0000:0000,
this value is optional.
When non-zero, this pointer wi II be used as pointer
to a RAM area where certain dynamic values are to
be saved. When in EGA operation this RAM area wi II
hold the 16 EGA palette regist80' values plus
the overscan value in bytes 0-16d respectively.
At least 256 bytes must be allocated for this area.
Alpha Mode Auxi I iary pointer
In i
t
i a I i zed to 0000: 0000, th i s va I ue is opt i ana I .
When non-zero, this pointer is used as a pointer
to a tables described as follows:
byte
byte
'Word
'Word
dword
byte
byte
bytes/cha racter
block to load, should be zero for normal
ope rat
ion
count to store,
should be 256d for normal
operation
character offset,
should be zero for normal
operat ion
pointer to a font table
1~s~};¥a~~: ~~~~mum
calculated value wi II be
used, else th
i
s va I ue wi I I be used
consecutive bytes of mode values for which
this font description is to be used.
The end of this stream is indicated by
8
byte code of
'FF'
Graphics Mode Auxi I iary pointer
Initialized to 0000:0000,
this value is optional.
When non-zero, this pointer is used
8S
a pointer
to a tables described as follo'Ws :
byte
word
dword
byte
displayable rows
bytes per character
pointer to a font table
consecutive bytes of mode values for 'Which
th i s font desc r i pt jon is to be used.
The end of this stream is indicated by a
byte code of
IFF'
IBM Enhanced Graphics Adapter 107
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