1. Welcome Hearth.com Guests and Visitors - Please enjoy our forums!
    Hearth.com GOLD Sponsors who help bring the site content to you:
    Hearthstone Soapstone and Cast-Iron stoves( Wood, Gas or Pellet Stoves and Inserts)
    Caluwe - Passion for Fire and Water ( Pellet and Wood Hydronic and Space Heating)

Computer-Any "Scuzzy"(SCSI) experts here???

Post in 'DIY and General non-hearth advice' started by keyman512us, Jun 2, 2007.

Thread Status:
Not open for further replies.
  1. keyman512us

    keyman512us Member

    Joined:
    Feb 27, 2007
    Messages:
    804
    Loc:
    North Worc. CTY MA
    Hey all...
    Hope everyone is enjoying the "off season" so far.
    I recently "acquired" an HP Kayak computer setup with SCSI "Scuzzy"...I'm slowly learning about this "new to me" technology. Anyone here on the forum familiar with this type of setup?? Any info on "where to look on the net" for good help?
    ...It boots up but doesn't recognize the (hard)drive....I've changed the address setting several times etc..

    Any pointers??

    ...I took it to "a local computer shop" that provided me with a hard drive...but they weren't "really up" on it...seeing as it is kinda old by todays' standards. It's got 512 (one card) and dual 450's...I was thinking of setting it up "in house" for use with digital pic's etc...

    Any help would be greatly appreciated...

    Helpful Sponsor Ads!





  2. webbie

    webbie Seasoned Moderator Staff Member

    Joined:
    Nov 17, 2005
    Messages:
    12,255
    Loc:
    Western Mass.
    Macs used to have 'em.

    The drives often need a "terminator" and also each item in the chain has a number - the computer is usually 0 or 1, and then the SCSI devices have to be others. CD-ROMs, scanners and other stuff is usually on the chain.

    http://computer.howstuffworks.com/scsi.htm

    Can't help you much more with the Windoz stuff, but that is the idea.
  3. wg_bent

    wg_bent Minister of Fire

    Joined:
    Nov 19, 2005
    Messages:
    2,248
    Loc:
    Poughkeepsie, NY
    SCSI is hardly new in any way. Most devices today are SCSI and perform better than IDE. So you have an IRQ conflict? Try changing that in the BIOS. Do you have the proper device driver? What kind of machine is it? PC? Mac? Running what OS?
  4. TMonter

    TMonter Minister of Fire

    Joined:
    Feb 8, 2007
    Messages:
    1,399
    Loc:
    Hayden, ID
    What did you want to know?

    I have a system I built that has several SCSI hard drives so I'm very familiar with how SCSI works.
  5. jjbaer

    jjbaer New Member

    Joined:
    Oct 24, 2006
    Messages:
    781
    Loc:
    OH
    Warren...you in a time loop....LOL.................90% of all computers sold today are PC's and most of them from 2 yre ago and going backwards have IDE's................even MAC's have IDE's........no way that SCSI drives outsell IDEs....
  6. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    SCSI is usually considered "server grade" hardware, and has the big advantage over IDE that it allows 8 or 16 devices (depending on the exact SCSI standard) per device chain, which makes it perfect for use in RAID arrays and the like. It also has performance advantages over IDE which get a bit arcane and mostly matter only if you are in a heavy multitasking / multithreaded environment with a lot of background disk I/O heavy tasks going on. IDE is cheaper "desktop" grade hardware. However IDE has arguably gotten better faster than SCSI, so there is less reason to prefer SCSI these days except for specialized server applications.

    To put it in woodburner terms, think of it as being like chainsaws - IDE = "homeowner grade" saws, and SCSI = "pro-grade" saws for BIG trees. Used to be the quality of the drives was significantly different, but there has been a lot of convergence so most times these days the same internals are used for both SCSI and IDE, and only the controllers are different.

    With SCSI there are a few problems - one is that there are a huge number of different SCSI standards that have evolved over the years, not all of which play nicely together, and some of which are totally incompatible and will cause smoke if connected...

    However it's a solvable problem.

    Start with the hardware configuration - if the hardware isn't right, it's possible nothing will work

    1. All the devices must be connected in a single, non-branching, chain.
    2. There must NOT be cable flopping around past the end devices unless the cable end is terminated.
    3. The END of each chain MUST be terminated, and there must NOT be a termination on any device in the middle of the chain.
    4. EACH device must have a UNIQUE ID number! By convention / custom, the controller is usually device ID 0, and the hard disks start at 1 and count up, (with the boot disk on ID 1) and tape drives start at ID 7 and count down, with CD's one number under the tapes, again counting down.
    5. The devices may appear on the chain in any order, and it is possible that a controller can drive some devices on an internal cable from one connector, and other external devices with another cable from a different connector as long as there is no branching.

    Termination on a drive may be done by a "SIP" resistor pack, a jumper or a dip switch. The ID is usually set by jumpers. There may be several other jumpers or switches that you will need to consult the manual for, but mostly are likely to be OK with the default settings.

    A device chain may also be terminated by a special "resistor plug" on the very end of the cable, in which case the drives should NOT be terminated.

    The controller may be configured by jumpers, switches or software. You will need to (again) check the manual for details / instructions.

    You may need to select IRQ's and address spaces for the controller - these must NOT conflict with other devices in the system (Note that as long as they are on different addresses and IRQ's, you can have as many SCSI controllers in the machine as will fit)

    Once you have the hardware right, power up the PC and go into the BIOS setup routines. In the PC BIOS, make sure that you don't have any non-existent IDE devices showing, and set to boot off the SCSI controller if you want to boot from SCSI. Note that if you have both SCSI and IDE drives in the same box, you must boot off the IDE drive. If you aren't using the IDE controllers, it is best to disable them.

    In most machines, there is a separate SCSI BIOS, on Adaptec controllers (perhaps the most common brand) most often are accessed by hitting "[CTRL][A]" at the SCSI BIOS prompt that will come up (hopefully) after the PC finishes its initial POST routine. Go into that BIOS and check to see if all the drives are recognized in the ways you expect, at the correct locations, etc. Resolve any hardware problems that show up at this point. A drive that is not recognized at this point will NEVER be seen, so this is a critical point. The drive MUST be recognized in HARDWARE or it will NOT be recognized in software!

    Most controllers will have a bunch of configuration options, set them appropriately per the manuals. Adaptec controllers have pretty good internal help functions, mostly with good advice... Pay special attention to things like OS type, the IRQ and interrupt settings, and any termination options.

    Once you have everything set up the way you think it should be, most controllers have a test option, go into that and verify that the controller passes the self test and any of the tests to other devices that it will perform (Adaptec controllers will only do internal tests w/ hard drives, other devices will come back with an error to the effect that the device is not a disk, this is normal. CAUTION - Some tests will destroy any data on the disk, it is good to run them if possible, but make sure you have backups. Also check the "empty" device numbers, make sure the controller doesn't think there is anything in them.

    Once all that happens exit from the controller BIOS (this will normally reboot the machine) and try to boot. After the initial PC BIOS self test, you should see the SCSI BIOS self test, which should list all the devices that the controller sees (which should be all of them) and then you will boot. Note that the SCSI drives may need to be partitioned, formatted and so forth before they are recognized by the O/S.

    If you are still having problems, remove all the drives, and see if you can make the controller work, then add the drives (w/ the system powered off) back one at a time. Dead drives can cause the chain to hang, but more common problems are either termination errors or ID conflicts.

    If you are still having problems, please post more info, especially the Controller make / model, whether it's on-board or an add-in card, the make and model numbers of each drive, and the way that you have them cabled and jumpered.

    Gooserider
  7. TMonter

    TMonter Minister of Fire

    Joined:
    Feb 8, 2007
    Messages:
    1,399
    Loc:
    Hayden, ID
    Actually IDE is going the way of the Dodo in favor of SATA.
  8. jjbaer

    jjbaer New Member

    Joined:
    Oct 24, 2006
    Messages:
    781
    Loc:
    OH
    I just knew you or someone else would bring up SATA's...LOL.... so that's why I said computers as of about 2 years ago and older....I've used both IDE and SCSI and it seems like the SCSI's are "built like tanks" and don't seem to ever fail but the IDE's go Tango Uniform much more often....anyone else feel that way too?
  9. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    If you look at the actual hardware and protocols, SATA is really just an advanced version of ATA / IDE, albeit with a different connector set.

    SCSI drives did tend to be more reliable than IDE drives, especially in earlier times. As I mentioned, SCSI and IDE stuff used to be built with different internal components in the actual drive housing itself, with IDE being built from "commodity grade" hardware, with price as a major issue since they were targetting a large consumer market that was highly price competive. SCSI drive guts were built with the premium "price no object" parts because their customers were after high reliability and performance, and were only minorly concerned about how much extra that quality cost... However as manufacturing techniques have improved, there has gotten to be less and less difference in the internal parts of the drives, and now many manufacturers will use the same drive body and guts for both lines, and only put a different interface card on the same chassis.

    Tape drives still have a big difference, but again it's largely a matter of price / performance - there is a need for very precise control over the tape movement, and in a consumer drive that is typically built into an expensive tape cartridge, driven by a very low cost drive. OTOH, server hardware will use an expensive high precision drive to operate a relatively low cost tape cartridge. (Not to mention that the server drive will typically be bigger and possibly more complex like the "tape jukeboxes" and the like....)

    So it's not just an opinion that SCSI is more reliable, there are engineering numbers to back it up!

    Gooserider
  10. begreen

    begreen Mooderator Staff Member

    Joined:
    Nov 18, 2005
    Messages:
    46,019
    Loc:
    South Puget Sound, WA
    Having fried a couple large SCSI Raid arrays I'm pretty neutral. I've had good luck with WD Enterprise level IDE and SATA drives.

    http://www.wdc.com/en/products/index.asp?cat=2
  11. restorer

    restorer New Member

    Joined:
    Aug 16, 2006
    Messages:
    831
    Loc:
    Salt Lake City, Utah
    Three years ago I had a chance to by Kayaks. They are installed originally at an educational institution and I was seriously looking for something a little more peppy than my old machine. I was pretty much told it's a whole different thought process in computing, but the Kayak was capable of multiprocessor installations, larger ram, bigger hdd's, and they could be linked in series given enough units you could have a hugely capable machine. The units available were used for graphic design and kicked butt on everything else.

    So, if you have the patience to understand the hardware, they are sweet machines. I have enough trouble understanding this simple unit, I wouldn't even try and tackle SCSI units. Although the school district has some very nice network servers on sale dirt cheap....... hhhmmmmm???
  12. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    Depends on what you are doing. If you are doing a fairly typical MS Windows type routine, you have fairly few tasks running, and they can mostly swap around without much impact that the user would notice. For this type of task mix, you will probably tend to be best off with a faster single processor machine, with a fast IDE / SATA drive, etc. A single user Linux box is about the same way.

    If you start doing certain specialty tasks that are highly parallelizeable such as certain forms of modeling, graphics rendering and other highly computation bound tasks, you start getting more benefit from multiple CPU's in a cluster setup. The key is the software has to be designed to parcel the jobs out into small tasks that can be passed around to the different CPU's, and the task has to be one that can be solved using parallel computation - if each step depends on the answer of the one before it, you can't go parallel.

    The other area where you can gain advantage by trading single high speed processors for lots of slower ones is the server environment where you have lots of tasks banging on the same resources at the same time, such as multiple users looking things up in the same database, or running multiple copies of the same program, etc. By parcelling out the jobs to different CPU's you can reduce the amount of time spent swapping, and allow more things to be done at the same time.

    SCSI tends to handle this sort of environment better because it is designed to handle lots of simultaneous I/O requests and interleave them using techniques like "elevator seeking". IDE (I'm not sure about SATA) handles requests one at a time, making later requests wait until the first one finishes each time... On a single user system this usually isn't a big issue, but on a server where lots of different users are going to be giving disk requests at the same time, the SCSI system will feel like it has a faster response.

    Bottom line is that a home user typically doesn't get a huge advantage from running server hardware. Of course there are exceptions, like trying to build a "media server" but that is a bit specialized.

    Gooserider
  13. Jags

    Jags Moderate Moderator Staff Member

    Joined:
    Aug 2, 2006
    Messages:
    14,648
    Loc:
    Northern IL
    Goose says:

    "SCSI tends to handle this sort of environment better because it is designed to handle lots of simultaneous I/O requests and interleave them using techniques like “elevator seeking”. "

    This was probably single handedly the biggest advantage of the SCSI drives vs. IDE or SATA. Gives ya a 2 way street for data traffic. The next big advantage was for the RAID configurations for server data security (safety) and swapable drives if (when) failure occurs.
  14. Eric Johnson

    Eric Johnson Mod Emeritus

    Joined:
    Nov 18, 2005
    Messages:
    5,705
    Loc:
    Central NYS
    Most everything I used to use SCSI devices for (scanners, ZIP drives, R/W CD drives) is now done faster and a whole lot easier with USB connections. SCSI could be tricky to set up, but was fast and bullet proof when you got it working right.

    Anybody wanna buy some SCSI hardware?
  15. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    Definitely true on the consumer level, arguable on the commercial production level. Also somewhat argueable as to whether USB or FireWire is better. OTOH you could do stuff with SCSI that you couldn't do with other hardware, like have drives connected to two different machines such that if the primary machine failed, it was still possible to access the data from the second machine - you want to talk about tricky setups?

    Frankly I think the big mistake was when they were first coming out with the hardware, they chose the wrong pronounciation for the acronym... If they had just pronounced it with a different vowel sound in between the first two letters, instead of the second and third letters, you would have hardware that everybody wanted, instead of stuff that sounded like it needed to be cleaned... Talk about a marketing goof!

    As to purchasing SCSI hardware - It's possible I might be interested depending on what it is, though I've got a small pile of it myself that I haven't bothered to set up (Mostly because I need 110VAC power supplies to replace the 48VDC supplies that are in the drive arrays) Probably wouldn't be able to offer very much, but would be willing to swap some UPS units I have...

    Gooserider
  16. Eric Johnson

    Eric Johnson Mod Emeritus

    Joined:
    Nov 18, 2005
    Messages:
    5,705
    Loc:
    Central NYS
    Alright, here's a computer trivia question for you from the (consumer) SCSI heyday:

    What does TWAIN stand for?
  17. BrotherBart

    BrotherBart Hearth.com LLC Mid-Atlantic Division Staff Member

    Joined:
    Nov 18, 2005
    Messages:
    27,293
    Loc:
    Northern Virginia
    Technology Without An Interesting Name
  18. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    The word TWAIN is not officially an acronym; however, it is widely known as a backronym for "Technology Without An Interesting Name". :p It's not really SCSI per se, though it could use SCSI, and at the time most TWAIN devices were using the SCSI bus, probably because it was the most common bus adapter type that had a bidirectional, high speed / high bandwidth capability and also a connector spec (actually several!) for connecting to devices external to the machine.

    It was a rather defective spec for defining the interface between a PC and "image acquisition devices" such as cameras and especially scanners. It had the problem that it was very tied to the manufacturers' GUI interfaces, making it difficult to write third party apps that used TWAIN devices.

    It has mostly been supplanted by "SANE" - "Scanner Access Now Easy" that defines a driver interface that is independent of any MFGR GUI, allowing third party software (IE graphics programs) to access SANE devices in a consistent manner, as a SANE device will always present the same interface regardless of what the driver has to do to talk to the actual hardware.

    (OK, I'll admit, I had to look it up...) Here's the Wikipedia entry, and here's the TWAIN Working Group if you want more details...)

    Gooserider
  19. Eric Johnson

    Eric Johnson Mod Emeritus

    Joined:
    Nov 18, 2005
    Messages:
    5,705
    Loc:
    Central NYS

    tru.dat, BB. You win.

    I got pretty productive in the mid '90s TWAINing scanned images into programs like PhotoShop and Word (OCR processing), but one day my computer apparently became "unTWAINed" and I never could get it working again.

    I remember the multiple connectors, Goose. You'd order a card or a peripheral and the damn thing would come with the wrong kind. I believe one had close to 100 pins, if not more.

    Gee, this is bringing back some memories. Remember "Plug and Pray?" That was the sure path to Atheism.

    Buddy of mine had a Mac back when USB first came out. His question always was "Oh yeah? Which universe?"
  20. Gooserider

    Gooserider Mod Emeritus

    Joined:
    Nov 20, 2006
    Messages:
    6,737
    Loc:
    Northeastern MA (near Lowell)
    Actually the connectors weren't that bad, it wasn't quite 100 pins... The HD connector used on ultra wide SCSI is 68 pins, which had some additional pins added when they created the SCA SCSI connector that put the power and drive selection onto the cable connector so that there was only one connector for the drive - which was really good for hot swap setups.

    The two sources that I use most for SCSI related lookups are SCSI Planet and Gary Field's SCSI FAQ Central Although neither looks like they are being really heavily maintained. (However both could be helpful in dealing with the original question.)

    Gooserider
  21. keyman512us

    keyman512us Member

    Joined:
    Feb 27, 2007
    Messages:
    804
    Loc:
    North Worc. CTY MA
    ...Just checking in...Thanks to everybody for taking the time to reply.

    I brought it to a "newly opened shop" and they took a quick look at it but didn't have much luck with it. I think they just might not have been "too up on what they were looking at".

    ...At any rate I bought a hard drive from them for "short money" and I'll be playing with the Kayak next really long boring rainy day....Not like I need another project...but it might become a welcomed "change of pace". I'm gonna approach getting it up and running...all in due time.

    I'll probably set it up in the "slowly becoming a new workshop" attic space...the "rainy day get-away spot".
Thread Status:
Not open for further replies.

Share This Page