Newsgroups: comp.sys.atari.st
Path: utzoo!utgpu!watserv1!watmath!ljdickey
From: ljdickey@watmath.waterloo.edu (L.J.Dickey)
Subject: Re: chaining hard drives to a 1040ST
Message-ID: <1991Feb14.201303.29667@watmath.waterloo.edu>
Keywords: ST, hard drives, chaining
Organization: University of Waterloo
References: <1991Feb13.183757.9927@cbfsb.att.com>
Date: Thu, 14 Feb 1991 20:13:03 GMT
Lines: 26

In article <1991Feb13.183757.9927@cbfsb.att.com> hojo@cbnewsb.cb.att.com
	(HC Johnson) writes:
>> What is the maximum number of hard drives that can be chained together
>> on a 1040ST (TOS 1.0)?  Is there any problem with having different sized
>> hard drives (e.g. 2 20meg and a 30meg)?  Is there a ceiling on the
>> amount of disk space TOS will recognize?  Is the number of partitions
>> limited only by the number of letters in the alphabet, or is there a TOS
>> limit on the total number of HD partitions?
>> 
>> Steve "Stevers!" Coile

>The TOS limit: 16 devices, of which 2 are the floppy drives.
>This leaves 14 HD partitions which can be active at one time.
>
>The 1040ST limit: At most 7 SCSI devices.  Most of these support
>2 Hard Drives, some 8.  Subtract 1 SCSI device for the (usual) clock,
>and you get 6, giving 12 to 48 drives maximum.
>
>The Atari Hard disk driver, AHDI, only supports 1 HD on each SCSI device.
>
>Thus TOS will access disk like devices as letters C thru P.

Thanks, Howard.   I would like to add that
there is another limit:  the size of each partition.
On early systems, 16 Megabytes per partition.