aidancaamano

Q: Macintosh Plus SCSI Hard Drive Problem

I have a Macintosh Plus with a Micronet Branded SCSI Hard Drive. I have a terminator for the drive. Once hooked up to the computer, I turn the drive on, then turn the Macintosh on. The Macintosh displays the blinking question floppy disk, as if the drive was not even connected. On the drive, the red light flashes for a split-second, every second or so. The green light stays off. The computer does not show an X on the floppy disk icon. I boot from the Micronet SCSI Utility Floppy disk, and the Hard Drive does not show up on the desktop. I go into the Utility, and it scans for drives. When it gets to id 6, which the drive is set to, I get an error, followed by the message "The Drive does not support Inquiry Command." What is inquiry command? I tried every drive id, in both SCSI ports on the drive. The terminator is properly connected. Is there something that I am doing wrong?

 

Thanks,

 

Aidan

Macintosh Plus 1MB Beige, Mac OS 8.6 or Earlier, Micronet Disk is running system 6

Posted on Apr 24, 2015 12:39 PM

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Q: Macintosh Plus SCSI Hard Drive Problem

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  • by JustSomeGuy,

    JustSomeGuy JustSomeGuy Apr 25, 2015 5:31 PM in response to aidancaamano
    Level 3 (586 points)
    Apr 25, 2015 5:31 PM in response to aidancaamano

    Sounds like the drive has gone bad.  Was it working before/recently?

  • by aidancaamano,

    aidancaamano aidancaamano Apr 25, 2015 11:21 PM in response to JustSomeGuy
    Level 1 (4 points)
    Desktops
    Apr 25, 2015 11:21 PM in response to JustSomeGuy

    The drive was like this when I bought it (it came as a bonus with the computer). Do you know what Inquiry Command is? There must be something I can do to fix it. What does it mean when it has "gone bad?" What would cause that? Is there anything special about Micronet drives?

  • by Jan Hedlund,

    Jan Hedlund Jan Hedlund Apr 28, 2015 3:47 PM in response to aidancaamano
    Level 6 (9,869 points)
    Apr 28, 2015 3:47 PM in response to aidancaamano

    The Inquiry command is used to request information from a SCSI drive. Depending on the drive, this could be things like manufacturer, model and disk data.

     

    Since you do get the error message, I assume that there is no way to update or reformat the hard disk using the existing floppy. Have you tested other disk utilities (the choice may be somewhat limited under System 6, though)?

     

    1 MB (RAM) is mentioned in the product list above. This is what the Macintosh Plus label normally says, but the maximum RAM is 4 MB. If the machine in fact has 2 MB or more RAM installed, System 7 can be used per se. However, because of the limited space on an 800K floppy, it is often complicated/difficult to modify a disk tools disk to hold various third-party utilities. It would help if you could locate an external  Zip 100 SCSI drive.

     

    The following web pages could possibly be of interest to you:

    http://macfaq.org/hardware/harddisk.shtml

    http://www.vintagemacworld.com/pluszip.html

     

    BTW, exactly which Micronet hard drive model is it? Also, is there a sound of the hard disk spinning?

     

    Jan

  • by aidancaamano,

    aidancaamano aidancaamano Apr 28, 2015 9:32 PM in response to Jan Hedlund
    Level 1 (4 points)
    Desktops
    Apr 28, 2015 9:32 PM in response to Jan Hedlund

    When I go to "about the finder" it says I have 1024 KB of RAM, which is 1 MB. The hard drive disk is most definitely spinning. On the back of the drive, the model is "MS." I do not have a Zip drive, or any third party disk utilities. I can't format the hard disk, since that option is greyed out. If Inquiry command is required for the drive to work, why wouldn't the drive support it? Is something broken in the drive? I took it apart once, saw some dust, cleaned it up, but that didn't fix anything.

  • by Jan Hedlund,

    Jan Hedlund Jan Hedlund Apr 29, 2015 8:06 AM in response to aidancaamano
    Level 6 (9,869 points)
    Apr 29, 2015 8:06 AM in response to aidancaamano

    A quick web search for "Micronet MS" resulted in the following example: http://www.applerescueofdenver.com/products-page/external-enclosures-scsi/micron et-ms-tape-drive-scsi/. However, that is a tape drive, so I guess that the "MS" is used for the external case only. Is there a model number or any other information on the hard drive itself, that apparently has been installed inside your case (instead of a tape drive, which obviously would behave in a completely different manner)?

     

    You mentioned that you took the drive apart. I assume that this was merely the external case. Taking a hard drive apart is not a good idea; microscopic particles on the disk(s) can ruin a drive.

     

    Jan

  • by aidancaamano,

    aidancaamano aidancaamano Apr 29, 2015 12:29 PM in response to Jan Hedlund
    Level 1 (4 points)
    Desktops
    Apr 29, 2015 12:29 PM in response to Jan Hedlund

    I actually just realized something. What I was hearing was the drive fan. When I manually stopped the fan, I heard nothing. I did not take the drive itself apart, just the casing. I see a number on the inside of the case, which reads "ST-157N." Below that is the Input Voltage/Amps. Next to it is a large "-0." What do I do if the hard disk is not spinning? I tried putting my finger in from of the fan, and turned it on. The drive made a small sound, but stopped. The problem is definitely in the drive or possibly the power supply.

  • by Jan Hedlund,

    Jan Hedlund Jan Hedlund Apr 29, 2015 1:01 PM in response to aidancaamano
    Level 6 (9,869 points)
    Apr 29, 2015 1:01 PM in response to aidancaamano

    That appears to be a Seagate drive (ftp://ftp.seagate.com/techsuppt/scsi/st157n.txt).

     

    It would probably not be a bad idea to check the DC output voltages from the power supply with a multimeter. Just a word of warning: Be careful! I do not know whether the power supply inside this case is completely open or somehow protected. In any case, do expect to find dangerous high-voltage AC circuits. If you have any doubt whatsoever about how to safely carry out measurements, do ask someone with the necessary expertise for help.

     

    Old hard disk drives sometimes suffer from "stiction" (try a web search for "hard disk stiction" for more information, and for some ideas how to attempt to solve the problem).

     

    Jan

  • by aidancaamano,

    aidancaamano aidancaamano Apr 29, 2015 1:28 PM in response to Jan Hedlund
    Level 1 (4 points)
    Desktops
    Apr 29, 2015 1:28 PM in response to Jan Hedlund

    Do you have any idea how to check the voltage using a multimeter? Is a voltmeter the same as a multimeter, since I only have a voltmeter? Also, the power supply is open, and there are no high voltages, since I touched every component while it was off, and did not feel anything.

  • by Jan Hedlund,

    Jan Hedlund Jan Hedlund Apr 29, 2015 1:57 PM in response to aidancaamano
    Level 6 (9,869 points)
    Apr 29, 2015 1:57 PM in response to aidancaamano

    The voltmeter is one part of a multimeter.

     

    You should be careful even if a device has been switched off. Capacitors can hold a charge for a long time. However, in this case I am more concerned about the fact that the SCSI drive enclosure (and thus the power supply) must be turned on in order to carry out any DC output voltage measurements, which could expose you to dangerous AC voltages as well. Since you are not sure about how to perform these measurements, I strongly recommend that you ask another knowledgeable person to help you. Do not proceed on your own!

  • by aidancaamano,

    aidancaamano aidancaamano Apr 29, 2015 2:26 PM in response to Jan Hedlund
    Level 1 (4 points)
    Desktops
    Apr 29, 2015 2:26 PM in response to Jan Hedlund

    I don't know anybody who knows how to check the voltage on an old hard drive. I could get someone to help me, but I would still need to know how to use the voltmeter on the drive and show them.

  • by Jan Hedlund,

    Jan Hedlund Jan Hedlund Apr 29, 2015 3:11 PM in response to aidancaamano
    Level 6 (9,869 points)
    Apr 29, 2015 3:11 PM in response to aidancaamano

    The idea would be to begin by establishing whether or not the SCSI enclosure is capable of supplying correct output voltages (5 VDC and 12 VDC). However, as indicated above, any work inside a case with an open power supply can be dangerous. Therefore, please understand that I do not want to post any details here. It is better if someone with the necessary expertise can carry out the measurements, or at least assist directly.

     

    An Internet search for "how to use a voltmeter" or "how to use a multimeter" should provide you with general information, if you wish to learn more about how to work with test instruments.