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02EB
2B FF
02ED
F3/
AA
02EF
02EF
4F
02FO
FD
02Fl
02Fl
8B
F1
02F3
8B CB
02F5
02F5
AC
02F6
32 C4
02F8
75 lE
02FA
SA
C2
02FC
AA
02FD
E2 F6
02FF
22 E4
0301
74 13
0303
SA
EO
0305
86 F2
0307
22 E4
0309
75 04
030B
8A 04
0300
EB EO
030F
030F
FC
0310
47
0311
74 DE
0313
4F
0314
EB 09
0316
0316
BO 00
0318
0318
FC
0319
C3
031A
= AOAC
= C460
= 00C8
= 8099
= B862
= 015E
= 015E
= 0043
= 0040
031A
031A
83 EC OA
0310
8B EC
031F
E8 0001 R
0322
BO 30
0324
E6 43
0326
BO 00
0328
E6 40
032A
F6 06 0487 R 02
032F
74 1 F
0331
E8 016B R
0334
C7 46 02 015E
0339
C7 46 04 8D99
033E
C7 46 06 B862
0343
B2 B4
0345
B4 01
0347
BO 27
0349
E8 OD18 R
034C
B2 BA
034E
EB 2A
0350
0350
E8 014B R
0353
E8 OE9C R
0356
73 11
0358
B2 D4
035A
B4 01
035C
BO 14
035E
E8 OD18 R
0361
C7 46 02 015E
0366
EB 06 90
0369
0369
C7 46 02 00C8
036E
036E
C7 46 04 AOAC
0373
C7 46 06 C460
0378
B2 DA
037A
037A
B8 0500
0370
CD 10
037F
2B C9
0381
0381
EC
0382
A8 08
0384
75 07
0386
E2 F9
0388
B3 00
038A
E9 044B R
0380
0380
BO 00
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
C
C
SUB
REP
01,01
STOSB
01 = OFFSET 0 RELAT I VE TO ES REG
WR I TE STORAGE LOCAT IONS
C
C3:
STGOl
PO I NT TO LAST BYTE JUST WR I TTEN
SET 0 I R fLAG TO GO BACKWARDS
C
C
DEC
STD
01
C
C4:
C
C
MOV
MOV
SI,DI
CX,BX
SETU P BYTE CNT
C
C5:
I NNER TEST LOOP
READ OLD TEST BYTE lSI
J+
DATA READ AS EXPECTED?
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
LODSB
XOR
JNE
MOV
STOSB
LOOP
AND
JZ
MOV
XCHG
AND
JNZ
MOV
JMP
AL,AH
C7
AL,DL
C5
AH,AH
C6X
AH,AL
DH,DL
AH,AH
C6
DL,AH
C3
NO - GO TO ERROR ROUT I NE
GET NEXT DATA PATTERN TO WRITE
WRITE INTO LOCATION JUST READ
DECREMENT COUNT AND LOOP CX
ENDING 0 PATTERN WRITTEN TO STG?
YES - RETURN TO CALLER WITH AL=O
SETUP NEW VALUE FOR COMPARE
MOVE NEXT DATA PATTERN TO DL
READ I NG ZERO PATTERN TH I S PASS ?
CONT I NUE TEST SEQUENCE TILL 0
ELSE SET
0
FOR END READ PATTERN
AND MAKE FINAL BACKWARDS PASS
C
C6:
SET 0 I R FLAG TO GO FORWARD
C
C
C
C
C
C
C
C6X:
CLD
INC
JZ
DEC
JMP
01
C4
01
C3
AL,OOOH
SET POI NTER TO BEG LOCAT I ON
READ/WR I TE FORWARD IN SlG
ADJUST POI NTER
READ/WR I TE BACKWARD IN STG
; AL=O DATA COMPARE OK
C
C7:
MOV
CLD
RET
ENDP
; SET
0
I RECT I ON FLAG BACK TO INC
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
STGTST
; ---------------
iG~
-
~~~
-
~
TT
~~~~iNT
-T
i;~
-----------------
~
~
1.
I NIT CRT TO 40X25 - Sn'
****SET TO MODE****
:
; 2. CHECK FOR VERT I CAL AND V IDEO ENABLES, AND CHECK
TIM I NG OF SAME
;
~: g~~g~ ~~~~
I
~~~E ~ Nri~~~~~T
AND I NTENS I FY DOTS
~
-
~:
-
~ ~: ~
-
~~
-
~~~~~
-= -
~~:~~~~~~~
-
:::::~~ -~?
-
~?~:::::-
-----
; _____ NOM I NAL T I ME IS B286H FOR 60 HZ.
; _____ NOMINAL TIME IS A2FEH FOR 50 HZ.
OAOACH
OC460H
CENAB PER FRAME EQU
MAX_VERTJ10NO
EQU
200
08D99H
EQU
eENAB PER FRAME equ
MENAB=PER=FRAME EQU
OB862H
350
350
TIM CTL
T I MERO
POD14
PROC
SUB
MOV
ASSUME
CALL
MOV
OUT
MOV
OUT
test
JZ
CALL
MOV
MOV
MOV
MOV
MOV
MOV
CALL
MOV
jmp
COLOR EGA V:
-
CALL
ca
I I
color_V:
jne
mov
mov
mov
ca I I
MOV
jmp
EQU
EQU
NEAR
SP,OAH
BP, SP
043H
040H
OS: ABSO, ES: ABSO
DDS
AL,OOl10000B
TIM CTL,AL
AL, DOH
TIMERO,AL
info,2
COLOR EGA V
ENV 3-
-
WORD PTRI BP I I 2
J,
MENAB_ PER_FRAME
WORD PTRI BP I I 4
J,
MAX_ VERT_MONO
WORD PTRIBPJ(6J.MIN_VERT_MONO
DL, CRTC_ADDR_B
AH, C HRZ DSP
AL,27H
-
OUT OX
DL, INPUT STATUS B
sho rt
common-
ENV X
brst det
co lor v
dl,crtc addr
ah,l
-
a
1,20
out dx
WORD PTRI BP
J
I 2
J,
eENAB_PER_FRAME ;
brst_color_v
MAX T I ME FOR VERT/VERT
(NOMINAL
+
10%)
MI N TIME FOR VERT/VERT
(NOMINAL -
10%)
NUM OF ENABLES PER FRAME
MAX T I ME FOR VERT /VERT
( NOM I NAL
+
10%)
MIN TIME FOR VERT/VERT
( NOM I NAL -
10%)
enhanced enables per frame
NUM OF ENABLES PER FRAME
8253 T I MER CONTROL PORT
8253 T I MER/CNTER 0 PORT
RESERVE 5 WORDS ON STACK
IN IT SCRATCH PAD POINTER
SET TIMER 0 TO MODE 0
SEND FIRST BYTE TO T I MER
SET UP I N MONOCHROME
NUM. OF FRAMES FOR MONO
MAX T I ME FOR VERT/VERT
MIN T I ME FOR VERT/VERT
MONO CRTC REG
HORIZ. TOTAL 01 PLAY
TO 40 COL
3BA
SET UP IN 40X25 COLOR
enhanced mode
no,40x25
brst mode on Iy!
hrz dsp end
modify for test only
NUM. OF FRAMES FOR COLOR
MOV
brst color v:
WORD PTRI BPJ(2],CENAB_PER_FRAME ; NUM.OF FRAMES FOR COLOR
-
MOV
COMMON:
MOV
MOV
MOV
INT
SUB
WORD PTRI BP)( 41, MAX_VERT_COLOR
WORD PTRI BP
J
161, M I N_ VERT _COLOR
DL, INPUT_STATUS
AX,0500H
10H
CX,CX
; ----- LOOK FOR VERT ICAL
POD14 1:
-
IN
TEST
JNE
LOOP
MOV
JMP
AL,DX
AL, 00001 OOOB
POD14 2
POD14-1
BL,OO-
POD14_ERR
;----- GOT VERTICAL - START TIMER
POD14 2:
-
MOV
AL,O
MAX T I ME FOR VERT/VERT
MIN T I ME FOR VERT /VERT
SET ADDRESSING TO VIDEO
ATTR STATUS
SET TO V IDEO PAGE 0
GET STATUS
VERT I CAL THERE YET?
CONTINUE IF IT IS
KEEP LOOK I NG TILL COUNT
EXHAUSTED
NO VERT I CAL
IBM Enhanced Graphics Adapter 113
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