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038F
E6 40
0391
2B DB
0393
33 C9
0395
0395
EC
0396
A8 08
0398
74 07
039A
E2 F9
039C
B3 01
039E
E9 044B R
03Al
03Al
2B C9
03A3
03A3
EC
03A4
A8 01
03A6
74 15
03A8
A8 08
03M
75 23
03AC
E2 F5
03AE
B3 02
03BO
E9 044B R
03B3
03B3
B3 03
03B5
E9 044B R
03B8
03B8
B3 04
03BA
E9 044B R
03BD
03BD
A8 08
03BF
75 F2
03Cl
03Cl
EC
03C2
A8 01
03C4
[1 FB
03C6
E3
FO
03C8
03C8
43
03C9
74 04
03CB
A8 08
03CD
74 02
03CF
03CF
BO 00
0301
E6 43
0303
3B 5[ 02
0306
74 04
0308
B3 05
030A
[B 6F
030C
030C
E4 40
030E
8A EO
03[0
90
03El
[4 40
03E3
86 EO
03E5
90
03E6
90
03E7
3B 46 04
03EA
70 04
03EC
B3 06
03EE
EB 5B
03FO
03FO
3B 46 06
03F3
7E 04
03F5
B3 07
03F7
EB 52
03F9
03F9
B8 090B
03FC
BB OOOF
03FF
B9 0050
0402
co
10
0404
EC
0405
52
0406
B2 CO
0408
B4 OF
040A
BO 3F
040C
E8 0018 R
040F
B8 OOOF
0412
5A
0413
0413
50
0414
52
0415
B2 CO
0417
84 32
0419
E8 0018 R
041C
5A
0410
58
041 E
2B C9
0420
0420
[C
0421
A8 30
0423
75 09
0425
E2 F9
0427
B3 10
0429
OA DC
042B
EB 1 E 90
042E
042[
2B C9
0430
0430
[C
0431
A8 30
0433
74 08
0435
[2 F9
0437
B3 20
0439
OA DC
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
12BO
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
C
C
OUT
TIMERO,AL
C
SUB
BX,BX
C
;----- WAIT FOR VERTICAL TO GO AWAY
C
XOR
CX,CX
C
P0014_25:
C
IN
C
TEST
C
JZ
C
LOOP
C
MOV
C
JMP
AL,OX
AL, 00001 OOOB
P0014 3
P0014-25
BL,OlH
P0014_ERR
;----- NOW START LOOKING FOR ENABLE TRANSITIONS
P0014 3:
-
SUB
P0014 4:
-
IN
TEST
JE
TEST
JNE
LOOP
MOV
JMP
P0014_4A:
MOV
JMP
P0014_4B:
MOV
JMP
CX,CX
AL,OX
AL,OOOOOOOlB
P0014 5
AL,00001000B
P0014 75
P0014-4
BL,02H
P0014_ERR
SEND 2ND BYTE TO TI MER TO
START IT
I NIT. ENABLE COUNTER
GET STATUS
VERT I CAL ST I LL THERE
CONTI NUE I FIT'S GONE
KEE P LOOK I NG TILL COUNT
EXHAUSTED
VERT I CAL STUCK ON
GET STATUS
ENABLE ON YET?
GOONIFITIS
VERTICAL ON AGAIN?
CONT I NU ElF
IT IS
KEEP LOOK I NG I F NOT
;
ENABLE STUCK OFF
; VERT I CAL STUCK ON
;
ENABLE STUCK ON
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
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
;----- MAKE SURE VERTICAL WENT OFF WITH ENABLE GOING ON
P0014 5:
-
TEST
AL,00001000B
JNZ
P0014 4A
; ----- NOW WA I T FOR ENABLE TO GO OFF
P0014 6:
VERT I CAL OFF?
GO ON I F IT IS
(ERROR I F NOT)
-
IN
AL,OX
GET STATUS
TEST
AL,OOOOOOOlB
ENABLE OFF YET?
LOOPE
P0014_6
KEE P LOOK I NG I F NOT
JCXl
P0014 4B
,
YET LOW
; ----- ENABLE HAS TOGGLED, BUMP COUNTER AND TEST FOR NEXT VERT I CAL
P0014 7:
-
INC
Jl
TEST
Jl
AL, 0000 1 OOOB
BUMP ENABLE COUNTER
I F COUNTER WRAPS,
SOMETH I NG I S WRONG
DID ENABLE GO LOW
BECAUSE OF VERT I CAL
; ----- HAVE HAD COMPLETE VERT I CAL-VERT I CAL CYCLE;
I F NOT, LOOK FOR ANOTHER
ENABLE TOGGLE
NOW TEST RESULTS
P0014 75:
-
MOV
OUT
CMP
J[
MOV
jrnp
P0014 8:
-
IN
POD14_9:
MOV
NOP
IN
XCHG
NOP
NOP
CMP
JGE
MOV
jmp
CMP
JLE
MOV
jmp
AL,OO
TIM CTL,AL
BX,WORD PTR(BPII2]
P0014 8
BL,05il
short pod14_err
AL, TIMERO
AH,AL
AL, TIMERO
AH,AL
AX, WORD PTR( BP II 4]
P0014 9
BL,06il
short pod14_err
AX, WORD PTR( BP II 6]
P0014 10
BL,07H
short
pod14_err
LATCH TIMERO
NUMBER OF ENABLES BETWEEN
VERT I CALS O. K.?
GET T I MER VALUE LOW
SAVE IT
GET T I MER HIGH
; MAXIMUM VERTICAL TIMING
MI N I MUM VERT I CAL TIM I NG
; ----- SEE I F RED, GREEN, BLUE AND I NT ENS I FY DOTS WORK
,
FIRST, SET A LINE OF REVERSE VIDEO,
I NTENSI
F
I ED BLANKS I NTO BUFFER
P0014 10:
-
MOV
MOV
MOV
I NT
IN
PUSH
MOV
MOV
MOV
CALL
MOV
POP
P0014 13:
AX,090BH
BX,OOOFH
CX,BO
lOH
AL,OX
OX
OL, A TTR_WR I TE
AH,OFH
AL,03FH
OUT OX
AX,OFH
OX
-
PUSH
AX
PUSH
OX
MOV
OL,ATTR_WRITE
MOV
AH,32H
CALL
OUT OX
POP
OX -
POP
AX
SUB
CX,CX
; ----- SEE I F DOT COMES ON
P0014 14:
-
IN
AL,DX
TEST
AL,00110000B
JNl
P0014 15
LOOP
P0014-14
MOV
BL,10il
OR
BL,AH
JMP
P0014 ERR
; ----- SEE I F DOT GOES OFF
P0014 15:
-
SUB
CX,CX
P0014 16:
-
IN
AL,OX
TEST
AL,00110000B
JE
P0014 17
LOOP
P0014::16
MOV
OR
BL,20H
BL,AH
WR I TE CHARS, BLANKS
PAGE 0, REVERSE VIDEO,
HIGH I NTENSI TY
80 CHARACTERS
SAVE I NPUT STATUS
A TTR I BUT E AOORESSS
PALETTE REG 'F'
TEST VALUE
VIDEO STATUS MUX
START WITH BLUE DOTS
SAVE
SAVE I NPUT STATUS
ATTR I BUTE AOOR[SSS
COLOR PLANE ENABLE
VIDEO STATUS MUX
RECOVER I NPUT STATUS
GET STATUS
~OT
THERE?
LOOK FOR DOT TO TURN OFF
CONT I NUE TEST FOR DOT ON
OR I N DOT BE I NG TESTED
DOT NOT COM I NG ON
GET STATUS
IS DOT STILL ON?
GO ON I F DOT OF F
ELSE,
KEEP WAITING FOR
DOT TO GO OFF
; OR I N DOT BE I NG TESTED
114 IBM Enhanced Graphics Adapter
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