| From: | Nick Lamburn |
| Date: | 16 Aug 2000 at 20:59:05 |
| Subject: | Re: A3000 SCSI hard disk problems |
Hi Tim,
>> 1. 2. 3.
>> +-+ +-+ +-+
>> |#|--------|#|-----------------------------------|#|
>> |#| |#| |#|
>> |#| |#| |#|
>> |#|--------|#|-----------------------------------|#|
>> +-+ +-+ SCSI CABLE +-+
>>
>>
>> 1 = Plugged into Hard Disk (where the older Quantum drive was)
>> 2 = Plugged into A3000's SCSI 50pin header
>> 3 = Spare, runs out to the front of A3000, above drive shelf.
>
> That isn't right - it leaves both ends of the SCSI chain unterminated,
> with the termination in the middle! A3000s often work like this, until
> suddenly you change something of no significance, then it decides not to
> work.
Like I say this is how it was when I got it, i'm sure of it. I mean yet i
did disconnect the cable, but i made sure it was put back as it was. And
like i say, the Quantum drive works if the SCSI Header is in Con 1. or 2.
when itself is in Con. 3. or 1. respectively.
>> There is no sign of any resistor packs on the motherboard behind the
>> SCSI
>> header, i couldn't remove the drive shelf because it's such a pain in
>> the
>> rear, but I'm guessing all are empty, because two of them are. Is this
>> good
>> or bad? :) If i do need this then i proves one thing, Amigas really are
>> girlfriends, always wanting your money...... :))
>
> If 2 are enmpty, it's fairly safe to assume that the other is too.
>
> What this means is that one end of the SCSI bus isn't terminated. As
> before, many A3000s work like this, but it isn't strictly correct.
And there was me hoping for a simple hard disk chnage over!! :))
>>> If not, then using a terminator on the external SCSI port may help.
>>
>> So if i was to get a passive or active terminator for the SCSI port,
>> then
>> that could help, or more prefrably would that solve this SCSI bus lock
>> up?
>
> A passive terminator would probably do for this configuration.
Which if this is the problem then that'd be cheaper :)
>> Thanks for the help. I'm going to try and fiddle with the SCSI cable
>> now.... :)
>>
>> Ok, just tried changing the cable as per the above diagram, connector
>> one
>> was attached to the SCSI header, Con. 2 to nothing and Con. 3 to the
>> hard
>> disk. SCSIMounter reports no change at all, yet placing the Quantum
>> drive
>> on Con. 3, worked! Grrr!
>
> It's sounding more and more like a problem with the drive itself...
Being it's either clapped out, or the jumpers are set wrong?? Which? :)
Regards
Quote carefully and read all ADMIN:README mails