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le9B
C3
lC9C
lC9C
lC9C
60 3E 0449 R 07
lCAl
77 16
lCA3
lCA3
52
1 CA4
B.A B800
lCA7
8E C2
lCA9
5A
lCAA
E8 1 B85 R
lCAO
26: SA 04
lCBO
22 C4
lCB2
02 EO
lCB4
8A CE
lCB6
02 CO
lCB8
E9 219B R
lCBB
lCBB
lCBB
80 3E 0449 R OF
lCCO
72 25
lCC2
E8 14F4
R
lCC5
72 20
lCC7
lCC7
E8 lC6F R
lCCA
E8 lC86 R
lCCO
OA 04
lCCF
DO E4
lCOl
OA 04
lC03
BO 02
lC05
E8 lC86 R
lC08
DO E4
lCOA
DO E4
lCOC
OA 04
lCOE
DO E4
lCEO
OA 04
lCE2
8A C2
lCE4
E9 219B R
lCE7
lCE7
lCE7
E8 lC6F R
lCEA
lCEA
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lCED
8A C8
leFF
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lCFl
OA 04
lCF3
FE CO
lCF5
3C 03
lCF7
76 Fl
lCF9
8A C2
lCFB
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lCFE
lCFE
lCFE
50
lCFF
8A 3E 0462 R
1003
53
1004
8A OF
1006
32 FF
1008
01 E3
100A
8B 97 0450 R
100E
5B
lDOF
3C 00
lOll
745C
1013
3C OA
1015
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1017
3C 08
1019
74 4C
101B
3C 07
1010
74 5C
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11)21
B9 0001
1024
CD 10
1026
FE C2
1028
3A 16 044A R
102C
75 35
102E
2A 02
1030
3A 36'0484 R
1034
75 28
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
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5364
5365
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5375
5376
5377
5378
5379
5380
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5400
5401
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5405
5406
5407
5408
5409
5410
5411
5412
5413
5414
5415
5416
5417
5418
C
C
RO_ 1 S
RET
ENDP
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: ----- READ DOT
AHO:
ASSUME
cmp
J8
READ_DOT
8
ssume
pUSh
s.rload
MOV
MOV
pop
CALL
MOV
AND
SHL
MOV
ROL
jmp
READ_DOT
cmp
jb
ca II
jc
READ DOT 1
-
ASSUME
CALL
CALL
OR
SHL
OR
MOV
CALL
SHL
SHL
OR
SHL
OR
MOV
JMP
READ_DOT _1
READ DOT 2
-
ASSUME
CALL
CALL
MOV
SHl
OR
INC
CMP
JBE
MOV
JMP
READ_00T_2
OS:ABSO
crt_mode, 7
r_l
PROC
NEAR
ds: absO, es: noth i n9
dx
es,Ob800h
OX,Ob800h
es,DX
dx
R3
AL,ES:[SI)
AL,AH
AL,CL
CL,DH
AL,CL
v ret
ENDP
crt_mode,Ofh
read_dot_2
mem det
read_dot_2
PROC
NEAR
DS:ABSO, ES: NOTH I NG
RD S
RD-l S
DL~AH
AH,1
DL,AH
AL,2
RO lS
AH~1
AH,1
OL,AH
AH,1
OL,AH
AL,DL
V Rn
ENOP
PROC
NEAR
OS:ABSO, ES:NOTHING
RO_S
RO lS
CL~AL
AH,CL
OL,AH
AL
AL,3
RD 2A
AL~OL
V RET
ENDP
OETERM I NE BYTE POS I T I ON OF DOT
GET THE BYTE
MASK OFF THE OTHER BITS IN THE BYTE
LEFT JUST I FY THE VALUE
GET NUMBER OF BITS I N RESULT
RIGHT JUST I FY THE RESULT
2 MAPS
4 MAPS
; -WR 7T[= T
T~
-----WR 7 T
[-T[~ET~;[
-TO -ACT 7 vE-;AG[ ------------------ ----------
j
TH I S INTERFACE PROV I DES A TELETYPE LIKE
I NTERfACE TO THE Y IDEO
:
CARD.
THE INPUT CHARACTER
IS WRITTEN TO THE
CURRENT CURSOR
:
POSITION, AND THE CURSOR IS MOVED TO THE NEXT POSITION.
iF THE
:
CURSOR LEAVES THE LAST COLUMN OF THE FIELD,
THE COLUMN I S SET
:
TO ZERO,
AND THE ROW VALUE IS INCREMENTED.
I F THE ROW VALUE
:
LEAVES THE FIELD,
THE CURSOR I S PLACED ON THE LAST ROW, FIRST
:
COLUMN,
AND THE ENTIRE SCREEN IS SCROLLED UP ONE LINE.
WHEN
:
THE SCREEN I S SCROLLED UP, THE ATTR I BUTE FOR F I Lli NG THE NEWLY
:
BLANKED LINE I S READ FROM THE
CURSOR POS I T I ON ON THE PREV I OUS
:
LINE BEFORE THE SCROLL,
I N CHARACTER MODE.
I
N
GRAPH I CS MODE,
:
THE 0 COLOR I S USED.
ENTRY
(AH I = CURRENT CRT MODE
(ALI = ·CHARACTER TO BE WRITTEN
NOTE THAT BACK SPACE, CAR RET, BELL AND LINE FEED ARE HANDLED
AS COMMANDS RATHER THAN AS DISPLAYABLE GRAPHICS
(BL I = FOREGROUND COLOR FOR CHAR WR I TE I F CURRENTLY I N A
; EXIT
GRAPHICS MODE
ALL REG I STERS SAVED
.
.........
--
......
-_
................
-_
.....
-_
........
--_
...........
--
---
......
--
-_
.....
--- ---_
...
--_
..
--_
............
-_
..
---_
.. ...
AHE:
ASSUME
PUSH
MOV
PUSH
MOV
XOR
SAL
MOV
POP
CS: CODE, OS: ABSO
AX
BH,ACTIVE_PAGE
BX
BL,BH
BH,BH
BX,1
OX, [BX
+
OFFSET CURSOR_POSN I
BX
:----- OX NOW HAS THE CURRENT CURSOR POSITION
CMP
JE
CMP
JE
CMP
JE
CMP
JE
AL,OOH
U9
AL,OAH
Ul0
AL,08H
U8
AL,07H
U11
: ----- WR I TE THE CHAR TO THE SCREEN
MOV
MOV
I NT
AH,10
eX,l
10H
:----- POSITION THE CURSOR FOR NEXT CHAR
INC
CMP
JNZ
SUB
CMP
JNZ
DL
DL,BYTE PTR CRT_COLS
U7
OL,DL
DH,ROWS
U6
: ----- SCROLL REQU I RED
SAVE REG I STERS
GET THE ACT I VE PAGE
SAVE
GET PAGE TO BL
CLEAR HIGH BYTE
*2 FOR WORD OFFSET
CURSOR, ACTIVE PAGE
RECOVER
I SIT CARR I AGE RETURN
CAR RET
I S IT ALINE FEED
LINE HED
I S IT A BACKSPACE
BACK SPACE
IS IT A 8ELL
BELL
: WRITE CHAR ONLY
ONLY ONE CHAR
WR I TE THE CHAR
TEST FOR COLUMN OVERFLOW
SET CURSOR
COLUMN FOR CURSOR
144 IBM Enhanced Graphics Adapter
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