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Offline xaccrocheurTopic starter

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SCSI basics
« on: March 28, 2003, 12:39:47 PM »
Hiya

On two of my drives I cannot select a LUN > than 4 !
I mean, if all SCSI peripherals are like this, this allows for only 4 units on the chain ?

What am I missing ?
 
The drive supplied with the Miggy is, interestingly enough, LUN1. Assuming that the GVP board has the LUN0, my CD-Rom works reliably when assigned LUN2.

At this point it boots and works like a breeze.

But when I plug the seagate, give it the LUN4 and remove the termination jumper on the Teac CD-Rom,

The machine boots, but presents a CD0:Uninitialized gray icon, and HDT now only sees 2 units, the Conner HD0&1 Drive, and a second with LUN4, I assume it's the Seagate but as usual, I can do nothing with it.

What gives ?
Is it really possible that this drive, the Seagate HAWK, something that costed a kidney when 1st available, A BIG server drive, only allows for the setup of the following LUNs : 1, 2, and 4 ?

I kid you not, here are the full specs of the drive

Besides, it uses a module, absolutely non-standard, that looks like a mini-PCI card slot, for termination purposes, amongst others, witch leaves me out in the cold since I don't have this module. However I used this drive a lot on various linuxboxes, and it has never complained about this so far.

And the IBM waiting to be integrated (what, I want to fully populate my SCSI chain !) only allows 0, 1, 2 and 3. Bah!

at least, this latter has a proper termination pinout.

My questions :
# HDToolBox, when he cares to start, offers the possibility of specify the LUN. In the software. Does that effectively change the LUN, or is it something else ?

# Can you affect the LUN in another way that the jumpers on the unit ?

# Since my system is working with HD0&1 as LUN1 and CD-Rom as LUN2 *[color=FF9900]no matter the termination jumper[/color][/b][/i]*,set or not on the CD-Rom, can I assume that my GVP HC+8 is "intelligent" enough to auto-terminate the chain ?

If you have read so far and care a little, you may have think that : Why does'nt this twit use the IBM drive to terminate his chain properly and give us a break.

I hear you, but no, the IBM drive, a very modern ultra-slim 4560MB SCSI  drive, does not permit the use of LUNs above... 3!

Am I stuck ? The window is open, should I jump ? :madashell:  :crazy:  :getmad:  :pissed:  :nervous:  :huh:  :shocked:  :cry:

Thanks anyway  8-)

pX
 

Offline pVC

Re: SCSI basics
« Reply #1 on: March 28, 2003, 02:14:36 PM »
Seems that you've understood wrong how those id-jumpers work. Those drives you have allow ID (LUN) 0-7. Some drives have those jumpers marked as bits 0,1,2 (and 3 on uw) and some as values 1,2,4, but they both work in same way. If there isn't no jumpers, then the unit is on id 0. If you put jumper on first place (marked as 0 or 1) then it's unit 1. On second place (marked as 1 or 2) it's unit 2.. and on third it's unit 4. Then you can use several jumpers and count the values of them together... like putting jumper on first and third place gives you 1+4=5 and putting jumper in all three place gives 1+2+4=7.

Maybe your problems are because you have set accidently two devices for same id.
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Offline vortexau

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Re: SCSI basics
« Reply #2 on: March 28, 2003, 03:28:53 PM »
Don't confuse ID values with LUN values; they are different things.

Referring to THIS Mounter scan of my Blizzard 2060 controlled devices:



You can see IDs numbered from 0 to 6. These IDs are commonly set with a set of jumpers consisting of SIX Pins using up to THREE Bridges in Binary Coding.

I seem to remember that the Controller itself takes ONE ID.

The only reference to LUN values that I have come across was in a CD-ROM Jukebox where the individual trays had differing LUNs.

 
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Offline iamaboringperson

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Re: SCSI basics
« Reply #3 on: March 28, 2003, 10:40:12 PM »
yes, i think you are confused...

LUN=Logical Unit Number - it usually cant be changed

you can change the physical address, & on narrow SCSI you can go from 0-7, the controlloer is usually 7



trust me, more than anything people call me the SCSI-KING!

 

Offline xaccrocheurTopic starter

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Re: SCSI basics
« Reply #4 on: March 29, 2003, 01:24:53 PM »
Quote

vortexau wrote:
(snip)
[/b] scan of my Blizzard 2060 controlled devices:

(snip)
 


WOW this is neat ! I can't believe that my machine is WORKING, when "mounter" is showing me nothing but a BLANK window, after scanning the bus !

Damn  :-x

pX
 

Offline xaccrocheurTopic starter

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Re: SCSI basics
« Reply #5 on: March 29, 2003, 01:38:16 PM »
Quote

pVC wrote:
Seems that you've understood wrong how those id-jumpers work.


yes I have, indeed.  :-) thanks for your explaination, I must have been drunk not to figure it out  :-D

Quote

putting jumper on first and third place gives you 1+4=5


Haha ! That was the trick ! How STUPID of me, that was close to OBVIOUS ! (sigh) :-D

Well I did what you advised, I now have a proper chain with :

GVP HC+8 Ser.II Rev.II (has a PSU socket, drains it from the ZII port)

TEAC SCSI CD-ROM x16
Conner CP30540 520 Mg SCSI HD (came w/ the machine I guess, am I correct ?)
IBM DDRS-HG 4560Mg SCSI HD
Seagate Hawk ST15230N (the BIG one, server stuff, double the thickness and heavy metal case)

But HDT still *refuses* to deal w/ my IBM and seagate drives !

And mounter's list is still VOID.  :-?

I managed to low-level-format the HAWK drive with the WB 3.1 HDT but that was all he allowed me to do, and errored when saving to drive table (ouch  :nervous: ) and now this : Nothing.

Oh, I must stress that at each boot, even despite this latter is currently very long, I always hot-reset the machine, not knowing if the drives are at full spinning speed when the WB needs them to.

After I have all setup (inch Allah), I know I can set the start and spinning times on the IBM and the HAWK using jumpers (yes !!) I I hope to eventually end up with one of the MAIN features I love the Amiga for : A FAAAST boot.

I'm starting to suspect my SCSI ribbon cable. It's a BIG one, full lengh allowing 7 units, like 1 meter long, been used for ages, all yellowed, maybe it's tired now.

I have this new one allowing only 3 units, will thoroughly test ALL the units with various settings. I *know* that SCSI heaven is at stake.

Thank you very much for your help. And for reading my bad english. i know it's painful, and really thank you all for your indulgence.

peace

pX
 

Offline Oli_hd

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Re: SCSI basics
« Reply #6 on: March 29, 2003, 04:35:42 PM »
Hi,

Quote
But HDT still *refuses* to deal w/ my IBM and seagate drives !
And mounter's list is still VOID.  


Remember you have to terminate the SCSI chain, the last drive must have the terminator on (Most drives have an internal one with a jumper to enable it)
 

Offline N7VQM

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Re: SCSI basics
« Reply #7 on: March 29, 2003, 07:07:25 PM »
Quote

xaccrocheur wrote:
I managed to low-level-format the HAWK drive with the WB 3.1 HDT but that was all he allowed me to do, and errored when saving to drive table (ouch  :nervous: ) and now this : Nothing.


Just a note:  Don't low-level format.  It's not needed.
And, in some cases (some Seagates)  the drive won't work after the low-level format.

Some years ago, I bought a 2GB Seagate Hawk (ST32155W).  It became a $300 paperweight after I performed a low-level format on it.  HDT refused to recognize it.  So, I called Seagates tech suport line.  After I finished telling the guy I had LLF'ed the drive he said, "Sorry, we can't help you.  You'll have to purchase another drive."
\\"...an error of 1 is much less significant in counting the population of the Earth than in counting the occupants of a phone booth.\\" - Michael T. Heath, Scientific Computing...