IBM XT 5160 Technical Reference page 274

;----- RESET THE DISK PARAMETER TABLE VECTOR
LINE SOURCE (B I OS FOR THE I BM PERSONAL COMPUTER XT) 1 1108/82
PC-XT System BIOS (11/08/82) 5-127
GO TO RES I DENT BAS I C
; ENABLE INTERRUPTS
; ESTABL I SH ADDRESS I NG
NEAR
18H
BOOT LOCN
ENDP-
WORD PTR DISK PO INTER. OFFSET DISK BASE
WORD PTR DISK=:POINTER+2.CS -
AX.AX
DS.AX
CS: CODE. DS: ABSO
OE6F2H
PROC
INT
MOV
CX.4
SET RETRY COUNT
IPL SYSTEM
PUSH
CX
SAVE RETRY COUNT
MOV
AH.O
RESET THE DISKETTE SYSTEM
INT 13H DI SKETTE 10
JC
H2 IF ERROR: TRY AGA IN
MOV AX.201H READ I N THE SINGLE SECTOR
SUB DX.DX
TO THE BOOT LOCAT I ON
MOV
ES.DX
MOV BX. OFFSET BOOT_LOCN
DRI VE 0. HEAD 0
MOV
CX.l
SECTOR 1. TRACK 0
INT 13H DI SKETTE
-
10
POP CX
RECOVER RETRY COUNT
JNC H4
CF SET BY UNSUCCESSFUL READ
LOOP
HI
DO I T FOR RETRY TIMES
LOAD SYSTEM FROM DISKETTE - - C X HA S RETRY COUNT
I F THERE I S A HARDWARE ERROR CONTROL IS
TRANSFERRED TO THE ROM BAS I C ENTRY PO I NT •
MOV
MOV
ASSUME
ORG
I PL WAS SUCCESSFUL
; - - - - - UNABLE TO I PL FROM THE DISKETTE
JMP
BOOT_STRAP
;--- INT 19 --------------------------------------------
BOOT STRAP LOADER
TRACK O. SECTOR 1 I S READ I NTO THE
BOOT LOCATION (SEGMENT 0, OFFSET 7COO)
AND CONTROL I S TRANSFERRED THERE.
BOOT STRAP
- STI
SUB
MOV
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433 HI:
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445 H2:
1446
1447
1448
1449
1450
1451
1452 H3:
1453
1454
1455
1456
1457 H4:
1458
1459
1460
E715 B90100
E718 CD13
E71 A
E71 A 59
E71B 7304
E71 D E2E5
E71F
E71F CD18
LOC OBJECT
E721
E721 EA007COOOO
E701 B90400
E704
E704 51
E705 B400
E707 CDI3
E709 720F
E70B B80102
E70E 2BD2
E7108EC2
E712 BB007C
E6F7 C7067800C7EF
E6FD 8COE7AOO
E6F2
E6F2 FB
E6F3 2BCO
E6F5 8ED8
E6F2