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IBM Personal Computer MACRO Assembler
Version 2.00
DSKETTE - -
0 I 110/86
0 I SKETTE ADAPTER B I OS
1-2
01-10-86
I
I
I
RESERVED
115
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5-24
(AH)=16 DISK CHANGE LINE STATUS
OUTPUT REG I STERS
(AH)
-
00 - 0 I SK CHANGE LI NE NOT ACTI VE
06 - 0 I SK CHANGE LI NE ACT I VE
&
CARRY BIT ON
( DL ) - DR I VE NUMBER
(0 - I ALLOWED, V ALUE CHECKED)
(AH) = 11 SET DASD TYPE FOR FORMAT
I NPUT REG I STERS
(ALl
-
00 -
NOT USED
01
-
DISKETTE 320/360K IN 360K DRIVE
02 -
DISKETTE 360K IN 1 .2M DRIVE
03 -
0 I SKETTE I. 2M I N I. 2M DR I VE
04 -
0 I SKETTE 720K
IN 120K DR I VE
( DL I
- DR I VE NUMBER
(0 - 1 ALLOWED, VALUE CHECKED;
DO NOT USE WHEN 0 I SKETTE ATTACH CARD USED)
(AHI = 18 SET MED I A TYPE FOR FORMAT
I NPUT REG I STERS
(CH I
- LOW ORDER 8 OF lOB I TS MAX I MUM NUMBER OF TRACKS
(CLl
- BITS 1
&
6 - HIGH ORDER TWO BITS OF MAXIMUM TRACKS
-
BITS 5 THRU 0 - MAX I MUM SECTORS PER TRACK
( DL I
- DR I VE NUMBER
(0 - 1 ALLOWED, VALUE CHECKED)
OUTPUT REG I STERS
(ES:DI)
- POINTER TO DRIVE PARAMETERS TABLE FOR THIS MEDIA TYPE,
UNCHANGED IF (AH)
I S NON- ZERO
(AHI
-
OOH, CY = 0, TRACK AND SECTORS/TRACK COMBINATION IS SUPPORTED
-
01H, CY = 1, FUNCTION IS NOT AVAILABLE
-
OCH, CY = I, TRACK AND SECTORS /TRACK COMB I NA TI ON I S NOT SUPPORTED
- -
-----
- -- - -
- -
-
-
-
-
-- --
- -
--
- - -
-------
----- - - - -
- -
- - - -
-
- - - -
----
-
- - -
--
--
-
- -------
DISK CHANGE STATUS IS ONLY CHECKED WHEN A MEDIA SPECIFIED IS OTHER
THAN 360 KB DR I VE.
I F THE 0 I SK CHANGE LINE I S FOUND TO BE
ACT I VE THE FOLLOW I NG ACT IONS TAKE PLACE:
ATTEMPT TO RESET 0 I SK CHANGE LI NE TO I NACT I VE STATE.
I F ATTEMPT SUCCEEDS SET DASD TYPE FOR FORMAT AND RETURN 0 I SK
CHANGE ERROR CODE
IF ATTEMPT FAILS RETURN TIMEOUT ERROR CODE AND SET DASD TYPE
TO A PREDETERMINED STATE INDICATING MEDIA TYPE UNKNOWN.
I F THE 0 I SK CHANGE LINE I N I NACT I VE PERFORM SET DASD TYPE FOR FORMAT.
DATA VAR I ABLE -- (110 I SK PO INTER
DOUBLE WORD PO I NTER TO THE CURRENT SET OF 0 I SKETTE PARAMETERS
OUTPUT FOR ALL FUNCT IONS
AH = STATUS OF OPERATION
STATUS BITS ARE DEF I NED I N THE EQUATES FOR (110 I SKETTE STATUS
VAR I ABLE I N THE OAT A SEGMENT OF TH I S MODULE
-
CY = 0
SUCCESSFUL OPERATION (AH=O ON RETURN, EXCEPT FOR READ DASD
TYPE AH= ( 15) ) •
CY = 1
FA I LED OPERAT I ON (AH HAS ERROR REASON)
FOR READIWR I TEIVER IFY
OS, BX, OX, CX PRESERVED
NOTE:
I F AN ERROR I S REPORTED BY THE 0 I SKETTE CODE, THE APPROPR I ATE
ACT I ON I S TO RESET THE 0 I SKETTE, THEN RETRY THE OPERAT I ON.
ON READ ACCESSES, NO MOTOR START DEL A Y I S TAKEN,
SO THAT
THREE RETRIES ARE REQUIRED ON READS TO ENSURE THAT THE
PROBLEM I S NOT DUE TO MOTOR START-UP.
LIST
; DISKETTE STATE MACHINE -
ABSOLUTE ADDRESS 40:90
(DRIVE Al
&
91
(DRIVE B)
.LlST
I
I
PRESENT STATE
000:
360K
IN 360K DRIVE UNESTABLISHED
001: 360K
IN 1.2M DRIVE UNESTABLISHED
010:
1.2M IN 1.2M DRIVE UNESTABLISHED
011: 360K
IN 360K DRIVE ESTABLISHED
100: 360K
IN 1.2M DRIVE ESTABLISHED
101:
1.2M IN 1 .2M DRIVE ESTABLISHED
I 10: RESERVED
1 I 1: NONE OF THE ABOVE
------>
MEDI AIDR I VE ESTABLI SHED
-------------->
DOUBLE STEPPING REQUIRED (360K IN 1.2M
DRIVE)
------------------------------>
DATA TRANSFER RATE FOR THIS DRIVE:
00: 500 KBS
01: 300 KBS
10: 250 KBS
1 1: RESERVED
LIST
STATE OPERATION STARTED -
ABSOLUTE ADDRESS 40:92
(DRIVE A)
&
93
(DRIVE B)
PRESENT CYLI NDER NUMBER -
ABSOLUTE ADDRESS 40: 94
(DR I VE A)
&
95
(DR I VE B)
DISKETTE (01/10/86)
- Quick Links:
- Section 1. System Board
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