IBM 5170 Technical Reference page 239

INPUT
NONE
OUTPUT
CY
=
0 SUCCESS
CY
==
1 FAILURE -- ERROR IS IN DISKETTE_STATUS
,~
~
~
, (AX) DESTROYED
OS1A
b;;;:STA;::;------p;OC----NEA;------------------------­
OS1A E8 OS3B R
CALL WAIT INT WAIT FOR THE INTERRUPT
OSlO
OSH
72
84
14
08
JC
MOV
J34 -
AH,08H
I F ERROR, RETURN IT
SENSE I NTERRUPT STATUS COMMAND
OS21 E8 03E2 R
CALL NEC_OUTPUT
OS24 E8 OS80 R CALL RESULTS READ I N THE RESULTS
0527 72 OA
JC J34 CHK2 RETURN
0529 AO 0042 R
MOV AL, NEC STATUS GET THE FIRST STATUS BYTE
052C 24 60 AND AL,060H ISOLATE THE BITS
052E
0530
0532
3C
74
F8
60
02
CMP
JZ
CLC
AL,060H
J35
TEST FOR CORRECT VALUE
I F ERROR, GO MARK IT
GOOD RETURN
0533
J34:
0533 C3
RET
RETURN TO CALLER
0534
0534 80 OE 0041 R 40
J35:
OR
DISKETTE_STATUS, BAD_SEEK' CHK2_ERROR
0539 F9 STC ERROR RETURN CODE
053A C3
RET
053B CHK_STAT_2
ENDP
WAIT_INT
THIS ROUTINE WAITS FOR AN INTERRUPT TO OCCUR
A TIME OUT ROUTINE TAKES PLACE DURING THE WAIT. SO
THAT AN ERROR MAY BE RETURNED I F THE DRIVE IS NOT READY
INPUT
NONE
OUTPUT
CY ""
a
SUCCESS
CY == 1 FAILURE -- DISKETTE STATUS IS SET ACCORDINGLY
(AX) DESTROYED ­
~A~;:-;N;:--------p~OC----NE;~------------------
053B
053B F. - STI TURN ON INTERRUPTS, JUST IN CASE
053C
50 PUSH AX SAVE REG I STERS
0530
53 PUSH BX
053E 51 ~M ~
•
053F F8
CLC CLEAR TIMEOUT I NO I CATOR
0540 B8 9001 MOV AX, 09001 H LOAD WA I T CODE AND TYPE
0543 CD 15 INT 15H PERFORM OTHER FUNCTION
0545 72 11
JC J 36A BYPASS TIM I NG LOOP 1FT I MEOUT OCCURRED
0547 B3 04
MOY BL,4
CLEAR THE COUNTERS
0549 33 C9
XOR CX,CX
fOR 2 SECOND WA
I
T
054B J36:
054B F6 06 003E R 80 TEST SEEK_STATUS, I NT_FLAG TEST FOR INTERRUPT OCCURRING
0550 75 OC JNZ
J37
0552
E2 F7
LOOP J36 COUNT DOWN WHILE WAITING
OSS4 FE CB DEC 8L SECOND LEVEL COUNTER
0556
75 F3
JNZ J36
0558 80 OE 0041 R 80 J36A:
OR
DISKETTE_STATUS, TIME_OUT; NOTHING HAPPENED
0550 F9 STC ; ERROR RETURN
OS5E J37:
055E 9C PUSHF ; SAVE CURRENT CARRY
055F 80 26 003E R 7F AND SEEK_STATUS,NOT INT_fLAG ; TURN OFF INTERRUPT FLAG
0564 90 POPF RECOVER CARRY
0565
59 POP CX :ECOVER REG I STERS
0566 5.
POP
8X
0567 58
POP
AX
.
0568 C3
RET
GOOD RETURN CODE COMES fROM TEST I NST
0569 WAIT
-
INT ENDP
;
-------------------------------
-- -
-----------­
DISK INT
;
INPU~
THIS ROUTINE HANDLES THE DISKETTE INTERRUPT
; NONE
; OUTPUT
; THE I NTERRUPT FLAG I S SET I S SEEK_STATUS
;
----------------------------------------------­
0569
DISK INT 1
PROC FAR
;»>
ENTRY POINT FOR ORG OEF57H
0569 FB
- STI
RE ENABLE INTERRUPTS
056A 1 E PUSH
OS !AVE REG I STERS
OS6B 50 PUSH
AX
056C E8 0000 E CALL 005 SETUP DATA ADDRESSING
056F 80 OE 003E R 80
OR
SEEK_STATUS, I NT_FLAG TURN ON I NTERRUPT OCCURRED
0574 BO 20
MOY AL,20H
END OF I NTERRUPT MARKER
0576 E6 20 OUT 20H,AL INTERRUPT CONTROL PORT
0578 B8 9101
MOY
AX,09101H
INTERRUPT POST CODE & TYPE
057B CD 15 INT 15M GO PERfORM OTHER TASK
0570 58
POP AX
RECOVER REG
057E 1 F
POP OS
.
057F CF IRET RETURN FROM INTERRUPT
0580
DISK_INT_1 ENDP
;
----------------------------------
-------
.-- -­
RESULTS
rHIS ROUTINE WILL READ ANYTHING THAT THE NEC CONTROLLER
HAS TO SAY FOLLOWING AN INTERRUPT.
INPUT
NONE
OUTPUT
CY "" 0 SUCCESSFUL TRANSFER
CY"" 1 FAILURE -- TIME OUT IN WAITING fOR STATUS
NEC STATUS AREA HAS STATUS BYTE LOADED
I
NTO IT
; {AHl DESTROYED
0580
kESULTS-PROC----NE;R--------------------------- ­
0580
FC CLO
0581
BF 0042 R
MOY
DI,OFFSET NEC_STATUS PO I NTER TO DATA AREA
0584 51 PUSH
CX
SAVE COUNTER
0585 52 PUSH
OX
0586 53
PUSH
8X
0587
B3 07
MOY
BL,7 MAX STATUS BYTES
; ------ WA I T FOR REQUEST fOR MASTER
0589 87 02 R10: MOV BH,2 HIGH ORDER COUNTER
058B J38:
INPUT_LOOP
OS86 33 C9
XOR
CX,CX COUNTER
0580 SA 03f4
MOY
DX,03f4H
STATUS PORT
0590
J39: WA I T FOR MASTER
0590 EC
IN AL,DX
GET STATUS
0591
A8 80 TEST AL,080H
MASTER READY
0593 75 10 JNZ J40A
TEST D I R
0595
E2 F9
LOOP
J39
WA I T=MASTER
0597
FE CF DEC 8M
DECREMENT HIGH ORDER COUNTER
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