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jlswartz
03-29-2001, 11:36 AM
I'm in the process of building a RAID in a Burly enclosure, and things are going very well. I'm having some trouble getting the LEDs to work and the external SCSI ID selectors to work... This is extremely minor, I could just ignore both, and may do just that, but I thought it anyone could tell me off hand what I'm missing here it would be kind of nice to have everything just so...

I'm using IBM UltraStars in a 5083.

I find the SCSI switches only having three connectors the most puzzling part. How does that work with 4 pin pairs and only 3 connectors?


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John Swartz
Deskey Associates
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kaye
03-29-2001, 11:54 AM
John,

Which IBM UltraStars? Exact model numbers? I can't answer about the Burly, have not put one together yet. k

jlswartz
03-29-2001, 12:04 PM
They are: DDYS-T18350s

Thanks.



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John Swartz
Deskey Associates
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kaye
03-29-2001, 01:21 PM
John,

Go here http://www.storage.ibm.com/techsup/hddtech/ddys/ddysjum.htm and there is a diagram of the LED jumpers for J4 and a description further down the page. Forget worrying about those resistors. You don't have to add resistors, they are internal. The +5V [1] is for your LED Anode or red colored lead. Someone told me that if you connect the leads backwards, no harm, just no lit LED. So I tried hooking up the LED backwards, and there is no harm. Hope this helps. k

jlswartz
03-29-2001, 01:36 PM
Thanks. I've got a continuous amber.... is that what it should be? I guess I was expecting green...

Anyway, thanks for the help with that, any suggestions on the SCSI ids?



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John Swartz
Deskey Associates
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kaye
03-29-2001, 02:20 PM
You are going to need help from magician or someone who has built up a Burly. I don't know why the LED color is amber. And setting the SCSI IDs with those switches, again you need someone with Burly experience. I just ordered a Burly a few minutes ago, but I'm no help now. Have you checked http://www.macgurus.com/graphics/mgscsiultraid1.html ? k

ChrisYip
03-29-2001, 02:42 PM
Hi..

I've built up a couple of Burly's - one - I didn't hook up the external SCSI indicators mainly because of the note on the Gurus's page about how difficult it can be to decipher.

As for the drive LED - be sure that you're not on the drive POWER pins - which would simply glow telling you that there is power to the drive, but on the drive ACTIVITY pins - those should blink whenever the on-board LEDs fire on the drive.

I have another enclosure with two drives in it - in one case, the drive light on the enclosure DOES blink while, in the other, the drive light is always on - no idea why that's the case excepet that perhaps that specific drive LED pins are tied into the drive power vs drive activity circuit.

kaye
03-29-2001, 03:31 PM
I remember now (after downloading the DDYS pdf file) what the problem is with IBM drives and those pins for an LED. They are dual purpose pins. The LED can tell you that the drive is powered up (LED would always be on) or it can tell you drive activity (LED on only when there is read or write).

A pain in the butt to set, and can only be changed in Mode Page Parameters. No Mac Mode Page Parameters application sees or looks for this parameter on Mode Page 0 (zero). IBM drives used to ship with the parameter set for drive activity, which is what you want, but I don't know now. IBM used to have a utility called CodeUpDate which would allow you to set the parameter for drive activity, but the utility is PeeCee. I tried to run it on Virtual PC but couldn't get it to work.

I have earlier 10k rpm IBM Ultrastars, the 9ZX and 9LZX, which ship set for drive activity, but a very hard freeze once caused the LED to go to continuous on (powered on). Some very nice lady gave me a tip that initializing the drive or just changing the driver to Intech's HD SpeedTools would revert the LED to drive activity. It worked. I then went back to my driver of choice and never had another problem with the LED. YMMV.

Oh, and your yellow color, is that because you are using a yellow LED? k

[This message has been edited by kaye (edited 29 March 2001).]

jlswartz
03-29-2001, 04:36 PM
The LED looked green when it was off, but when on it looked yellow. So, I pulled out the power LED, and compared them... Aha! The power one is green, the drive ones are only sort of green... Which I suppose means they're yellow. So, I guess I'll hook 'em up and use them to indicate which drives are powered up, but I don't think it's worth going through a lot of mode page stuff, esp. if there's no Mac client to set it...

As far as the SCSI thing goes, I've just this minute figured that out.

Here's the deal for future reference:

The Burly enclosure has 3 connectors per switch. If you pull off the *switch* end connector and examine it closely (as mentioned in the Guru article) you'll see a little arrow pointing at one wire. (In my case the brown one.) Look at your three connectors, two have two wires, and one has only one... (a black one in this case which makes sense in retrospect) If you look closely at the pdf manual for the Ultrastar, it shows the pins like this:
1 3 5 7 9 11 13
2 4 6 8 10 12 14

On the bottom of the drive it merely shows 7-13 as the SCSI ID pins, which just to really confuse matters, it numbers 1-7 the other direction...

Again, looking at the manual, you'll see that 5,7,9,11,and 13 are all grounds, while 8,10,12, and 14 are the SCSI ID pins. Ordinarily you would jumper between each of these pins and the adjoining ground. To use the switch, line up the indicated colored wire (the brown in my example) with pin 8, which corresponds to SCSI ID bit 0. Set the connector sideways, and put the second half of that connector (on mine a red wire) on pin 10. Now orient the other connector in the same direction and apply it to 12 and 14. This leaves you the connector with the single black wire, it may be applied to any of the grounded pins, 7,9,11,or 13.

I find them a little loose, and will probably use some adhesive.

Hope that helps someone someday.

Note: I don't have any special knowledge of this, I just played with it until it worked, your mileage may vary.



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John Swartz
Deskey Associates
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magician
03-29-2001, 06:30 PM
guys, my regrets for coming late to the party....been very, very busy here lately, and haven't surfed the forums in awhile.

K, that's a beautiful tip about the mode pages! I need to remember that!

here's the deal on the enclosures and the ID connectors.

1. look at the wires inside the enclosure, and note where they interface with the plastic switch itself from the INSIDE of the enclosure.

2. the wires will be oriented vertically. What you want to do is note the order of the wires. For example, if the bottom-most wire is red, that will be your 0-wire. The second from the bottom, for purposes of this discussion, might be brown. That wire is your 1-wire. You continue upwards until all wires are counted. A common pattern is red-brown-yellow-grey, for example. The thing to remember here is, count from bottom to top, where the wires attach to the switch.

3. now, if you look at your ID pins on your drive, they are typically identified 0-4, or 1-4. Guess what? You got it. Each wire has its appropriate pin.

http://macgurus.com/infopop/emoticons/icon_smile.gif

in the case of Seagate drives, you use the ID pins on the rear of the drive between the power connector and the SCSI connector. The ID pins are the top pins farthest to the right, with the farthest pin to the right being--guess what? --the 0-pin.

http://macgurus.com/infopop/emoticons/icon_wink.gif

you attach your connectors from right to left on Seagate drives, 0-4, on the 0-4 pins.

the ground wire, the black, goes on the ground pin, which in the case of Seagate drives is the second from the LEFT on the lower row.

For IBM drives, the principle still applies: count from bottom to top on the switch in the backplane. The bottom wire goes on the 0-pin, and you continue upwards in sequence. The black wire, which is always the top wire, goes on the ground. That will handle ID's.

for LEDs.....mode pages are one way of handling it. It may also be possible to set the drives to use different ground pins on the front to get the lights to flash to reflect drive activity.

there is, indeed, one LED that should be attached to the power supply. That one shows when the enclosure is powered on. The other LED's are for drives, and generally are set to reflect drive activity, not drive power. It's your call.

one of the little final touches we use here is to lightly dab a bit of hot-glue on the LED wires and the ID connectors to secure them in place. Nothing sucks more than moving an enclosure and having something fall off.

one last tip: ALWAYS test before you hot-glue. Once you are SURE you have it right, THEN glue. Do not get overconfident and think "I got it, I can glue ALL these wires." I guarantee you will get caught, and have to disassemble the entire damned enclosure to fix one wrong wire, and it will be on your bottom drive.

http://macgurus.com/infopop/emoticons/icon_smile.gif

hope this helps, rather than confuses?