Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!hplabs!hp-pcd!hpcvlx!daveg
From: daveg@hpcvlx.cv.hp.com (Dave Guggisberg)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Fixed Disk Base Tables on PC/XT
Message-ID: <101000068@hpcvlx.cv.hp.com>
Date: 12 Sep 89 16:42:49 GMT
References: <29216@news.Think.COM>
Organization: Hewlett-Packard Co., Corvallis, OR, USA
Lines: 28


In my copy Interrupt List 489 under INT 41 it has: 

INT 41 - FIXED DISK PARAMETERS (XT,AT,XT2,XT286,PS except ESDI disks)
offset  Size    Description
00h     WORD    cylinders 
02h     BYTE    heads
03h     WORD    starting reduced write current cylender (XT only, otherwise 0)
05h     WORD    starting write pre-comp cylender
07h     BYTE    maximum ECC burst length
08h     BYTE    control byte
           bits 0-2: drive option (XT only, 0 otherwise)
           bit 3:    set if more than 8 heads
           bit 4:    always 0
           bit 5:    set if manufacturer's defect map on max cylender+1
           bit 6:    disable ECC retries
           bit 7:    disable access retries
09h     BYTE    stardard timeout (XT only, otherwise 0)
0Ah     BYTE    formatting timeout XT only, otherwise 0)
0Bh     BYTE    timeout for checking drive (XT only, otherwise 0)
0Ch     WORD    landing zone (AT/PS2)
0Eh     BYTE    sectores/track (AT/PS2)
0Fh     BYTE    0

Dave Guggisberg
daveg@cv.hp.com