Path: utzoo!attcan!uunet!snorkelwacker!bloom-beacon!eru!luth!sunic!ericom!juno11.ericsson.se!etxtorn
From: etxtorn@juno11.ericsson.se (Thomas Tornblom Konsult TM/JU 99367)
Newsgroups: comp.sys.mac.hardware
Subject: Re: How many terminators with 2 SCSI drives?
Keywords: SCSI terminators
Message-ID: <1990May31.115835.5918@ericsson.se>
Date: 31 May 90 11:58:35 GMT
References: <1654@ac.dal.ca> <8257@brazos.Rice.edu>
Sender: news@ericsson.se
Organization: Ericsson Telecom AB, Stockholm, Sweden
Lines: 26

In article <8257@brazos.Rice.edu> robbins@owlnet.rice.edu (Thomas Robbins) writes:
>In article <1654@ac.dal.ca> ireland@ac.dal.ca writes:
>  [deleted]
>/All the rest (six) said I had a termination problem, and that only the last
>-drive in the daisy chain was supposed to be terminated.  Is this right?
>\In my Jasmine Owner's Guide, it says that both ends of the chain are to be
>|terminated, so one doesn't start removing terminators until the third SCSI
>/device is added.  What's the scoop on terminators?  One at the end or one at
>-each end?
>\
>|Thanks,  Keith Conover
>/Keith@ac.dal.ca
>
>Your confusion here is caused by the fact that the Macintosh itself is one
>"end" of the daisy chain, with its own internal termination. You therefore
>start removing terminators once the **second** SCSI device is added. Your
>first SCSI device is actually the middle of the daisy chain, and having
>an external terminator attached to that device will do many interesting 
>things to your Mac, none of them good.

Well, the mac+ is kind of an exception in the sense that it lacks internal
SCSI termination. Therefore the first AND the last SCSI unit should be 
terminated and no other unit.

All macs with built-in HD have the drive terminated and needs termination
only in the last unit in the external chain.