From: adrie@ica.philips.nl (Adrie Koolen) Subject: Re: Adaptec 1542B vs 1542C vs 1740 Date: Wed, 22 Sep 1993 07:02:53 GMT
In article <27ndk5$9d5@track.taz.de> buk@taz.de ($ Burkhard Kohl) writes:
>$ Burkhard Kohl (buk@taz.de) wrote:
>
>: Well the 1542C supports SCSI-2 whereas the B does not. Furthermore 1542C allows
>: you to enter the SCSI-select program for test and configuration purposes from
>: ROM at boot time, so you don't need SCSI-select utilities :-)
>: --
>
>Sorry, but thats just wrong. Of course both adaptors are SCSI-2. Sorry again.
>To prevent being flamed I'll withdraw my stupid statement
I'll repeat it for the n-th time. The 1542B hasn't been made (I think) to be
SCSI-2 compatible, but the 1542B does implement all the mandatory SCSI-2
features that were optional in SCSI-1. These extra features are hardly worth
mentioning, because almost every contempory SCSI controller (except the old
Atari ST and perhaps the older Macs) does implement those extra features.
Note that Fast and Wide SCSI-2, Command Queuing and Asynchronous Event
Notification are optional in SCSI-2 and the 1542B does not support ANY of
the optional SCSI-2 features. Neither does the 1542C, I believe.
So the fact that the 1542B may be called SCSI-2 compatible doesn't buy you
much. Actually, I advise not to buy any SCSI device that isn't SCSI-2
compatible as a SCSI device that doesn't allow arbitration or the extended
sense data option might not work in your computer system. But don't think
that a SCSI-2 device will be faster than a SCSI-1 device, although it
certainly might be faster, but check it out first!
Adrie Koolen (adrie@ica.philips.nl)
Philips Consumer Electronics, Eindhoven, the Netherlands